The State of Play at Hogwarts
Quidditch is the principal wizard sport and the school sport of Hogwarts, so given the outstanding natural abilities of J.K. Rowling’s main protagonist, it unsurprisingly forms a major recurring element in the series, including an eventful visit to the Quidditch World Cup in Goblet of Fire.
The four houses of Hogwarts play an annual roundrobin tournament in which each house plays all of the others once during the course of the year, so that a member of a house team will play a maximum of three games, and there will be at least three games at which he or she may only be a spectator. A roundrobin tournament is the simplest and fairest type of competition in which each of the matches can influence the overall outcome of the Quidditch Cup to the same degree.^{[1]}
In Harry Potter’s first year at Hogwarts he immediately becomes the youngest Gryffindor player in a century (making his début at the age of eleven years, three months and several days), as Professor McGonagall intercedes with the headmaster to relax the rule preventing firstyear students from playing the sport competitively; presumably the rule has been in existence for that length of time, if not longer. Although Gryffindor already has a new Captain after Charlie Weasley’s departure, they also desperately need a Seeker of similar talent.
In fact the first book, Philosopher’s Stone, doesn’t allow the reader to see through Harry’s eyes how a full season of the Quidditch tournament is played out. There is no mention at all of the three games not involving Gryffindor. In the first match of the season, sometime after the start of November, Gryffindor narrowly defeats Slytherin, 170 points to 60 (PS11). The next logical game to be played in roundrobin format would be Hufflepuff versus Ravenclaw, involving the two other teams that have not yet played in the first round: it is fairly safe to assume that this was the second match of the season, or else Harry would have had the opportunity to see how the game was played, before he had a chance to play it himself. The remaining rounds of the tournament take place in the new year after the Christmas break.
We may surmise from chapter 13 that in the third match of the season Slytherin defeated Ravenclaw by a much wider scoring margin than either of the previous matches, to explain George’s comment that a Gryffindor victory over Hufflepuff in the fourth match would allow them to overtake Slytherin in the House Cup.^{[2]} Indeed, Harry wins the match so quickly that Professor Snape, as substitute referee, has hardly any time to influence the outcome by awarding a sufficient number of penalties to Hufflepuff.
There is some question as to the extent that points scored in the Quidditch Cup contribute to the House Cup. In chapter 11 of Chamber of Secrets Percy Weasley tells Harry his capture of the Golden Snitch contributed fifty points to the House Cup, or one third of its normal Quidditch score. So does goal scoring count for anything at all, and if so, by how much? Surely not on a onetoone basis; perhaps goals are credited only to the winning team, or the score is based on their margin of victory?
The only other evidence in the books that Quidditch matches influence the annual House Cup appears in Philosopher’s Stone, again citing fifty points for the capture of the Snitch, when Professor McGonagall docks that amount from Gryffindor:
“Fifty?” Harry gasped—they would lose the lead, the lead he’d won in the last Quidditch match (PS15).
And that is almost the last we hear of the Quidditch tournament for that year, as J.K. Rowling powers through to the conclusion of the main storyline; when Ron catches up with Harry in the infirmary during Chapter 17 the final result is mentioned almost casually, en passant. (The reference is so casual I continually overlooked it while drafting this essay.) There is subsequently a belated recounting of the end of the season in Chamber of Secrets, chapter 7. In match five, we may infer that Slytherin defeated Hufflepuff, so finishing the season with two wins from three matches. As for match six:
[Harry] had been unconscious in the hospital wing for the final match of the previous year, meaning that Gryffindor had been a player short and had suffered their worst defeat in three hundred years (CS7).
We might guess the Slytherins attempted to bribe Ravenclaw to unduly prolong the match, thus gaining the maximum advantage from scoring goals with the Quaffle before obtaining the Golden Snitch; had Ravenclaw defeated Hufflepuff back in match two, then the same tactics ought to have won the Quidditch Cup for Ravenclaw instead. Thus Hufflepuff must have won match two, and finished the season with one win from three matches, along with Ravenclaw. With Slytherin and Gryffindor level on two wins apiece, the Quidditch Cup is then decided by some comparative scoring system.^{[3] }Gryffindor’s heavy loss to Ravenclaw must have far outweighed both their victories, resulting in Slytherin winning the Cup (possibly for the sixth year in succession, if their supremacy in the House Cup carries over to Quidditch).
It would not seem fair that a team that won all three matches by narrow margins could lose the Cup to a team that had won only one match, but were victors by a huge margin over a side compromised by injury (e.g. Gryffindor only able to field six players, and without a Seeker); however if cumulative points are the only arbiter, then such a result is possible. (Indeed a team could lose all of its matches by large margins and yet have the highest season aggregate!) Therefore the rankings for the Quidditch Cup must order teams by the greatest number of victories, only then separating teams with equal numbers of wins, most likely by their accumulated points difference. Gryffindor’s heavy defeat in match six would most likely result in the Quidditch Cup order of Slytherin first (two wins), Gryffindor second (two wins), Ravenclaw third (one win) and Hufflepuff fourth (one win).
As some proportion of points scored in the Quidditch matches contributes towards the House Cup, along with points awarded to or penalised from students in all other ways throughout the school year, then the winner of the Quidditch Cup is slightly more likely to win the House Cup also. It is a mistake though to presume that victory in either Cup completely determines the outcome in the other competition. In the House Cup only the total number of points matters, so the number of victories has no intrinsic effect on the rankings.^{[4]} Before Professor Dumbledore’s final allocation of points, Slytherin have 472 points, Ravenclaw have 426 points, Hufflepuff have 352 points, and Gryffindor have 312 points. Philosopher’s Stone ends on a high note with Gryffindor coming from behind to overtake Slytherin in the House Cup (PS17).
Curiously (from a view of the narrative) the final match of the Quidditch season is played in the week after the finish of exams, when evidence in other books points to the final match occurring before exams. (Surely without any classes to be held and no more exams, it would have been a more likely sequence of events for the endofyear feast to have followed on immediately, and then for the students to be sent home? But this would have upset Rowling’s denouement, so it didn’t happen that way!) This reluctance to have Harry play the final Quidditch match appears to be the first manifestation of the increasing length to which Rowling goes to prevent her best creation from actually playing the sport at which he would seem to be the ideal player: in most of the games that follow, Rowling is prone to “tweak the circumstances” sometimes for but mainly against Harry. Quite rightly, she does not want her novels to appear as a series of six Quidditch match reports, interspersed with other happenings!^{[5]}
In Harry’s second year, the tournament is called off as Gryffindor are about to take the pitch for their second match of the season [CS14]. Success finally comes Gryffindor’s way in Harry’s third year (PA15), after a nasty scare with Dementors which allows Cedric Diggory to take the Snitch for Hufflepuff in the first match (PA9). In Harry’s fourth year, the Triwizard Tournament completely replaces the Quidditch Cup, and in his fifth year the Weasley twins and he are given “life bans” by the Hogwarts High Inquisitor for a postmatch indiscretion (OP19) that rules them out for the season. After being appointed Gryffindor’s Quidditch captain in sixth year, Harry plays for barely longer than a single game (HBP14), being rendered unconscious at the outset of one game (HBP19) and suspended on detention for another (HBP24); depending on how events unfold in the final novel, there is no ironclad guarantee that Harry will return to Hogwarts for all of his seventh year, or that Hogwarts will even remain open if the Board of Governors decide the school is too dangerous a target for Voldemort.^{[6]}
Hogwarts Quidditch Results by Season
Y10/11 : Y11/12 [PS] : Y12/13 [CS] : Y13/14 [PA] : Y14/15 [GoF] : Y15/16 [OP] : Y16/17 [HBP]
In the tables that follow, the outcomes of Quidditch matches that are not known directly but only by inferences are listed with an asterisk in the column marked Reference: in Harry’s first year at Hogwarts this applies to all of the matches not involving Gryffindor. Otherwise, book and chapter are cited for match results. The exact or approximate scores, are given where known: sometimes Rowling will have a character report a partial score during a match, and shortly thereafter the Golden Snitch will be caught, allowing the final score to be deduced. On other occasions we are only given the victory margin: from the analysis of HalfBlood Prince it seems clear that the victory margin helps the victor, and hinders the loser in the overall season.
The names of the house teams are denoted by their respective first letters. Positions are specified as follows: the Quidditch Captain is denoted +; Beaters are represented by b, Chasers by c, the Keeper by k, the Seeker by either s, or by § if he or she captures the Golden Snitch, and r denotes a reserve player. Goals scored by players are indicated after their name (it is unusual to be able to discern from the narrative who scored every last goal).
School year immediately preceding Harry Potter and the Philosopher’s Stone [PS–1 = Y10/11]
Match 
Victor 
Loser 
Reference 

1 
Gryffindor 
Hufflepuff 
PS9 * 
G: §: +Weasley C; c: Johnson, 2 others; b: Weasley F & G; k: Wood  
2 
Ravenclaw v Hufflepuff 

3 
Slytherin v Ravenclaw 

4 
Ravenclaw 
Gryffindor 
PS9 * 
G: s: unknown; c: Johnson, 2 others; b: Weasley F & G; k: +Wood  
5 
Slytherin v Hufflepuff 

6 
Slytherin 
Gryffindor 
PS9 * 
G: s: unknown; c: Johnson, 2 others; b: Weasley F & G; k: +Wood 
Rankings: probably 1st, Slytherin (at least 2 victories); probably 2nd, (at least 1 victory); probably 3rd, Gryffindor (1 victory); probably 4th, Hufflepuff.
From the comment by Professor McGonagall quoted above, the final match of the season was Slytherin v Gryffindor, or in other words the season had been played out of normal order, as was the case in Prisoner of Azkaban. Thus Charlie Weasley played in the victory over Hufflepuff in the first match of the season, and Gryffindor then went on to lose its remaining matches against and Slytherin without him. With one victory, Gryffindor were at least spared the indignity of finishing last in the Cup (see HBP24).
Harry Potter and the Philosopher’s Stone [PS = Y11/12]
Match 
Victor 
Loser 
Reference 


1 
Gryffindor 
170 
Slytherin 
60 

G: §: Potter; c: Johnson 1, Spinnet, Bell; b: Weasley F & G; k: +Wood S: s: Higgs; c: +Flint 6, Pucey; k: Bletchley 

2 
Hufflepuff 
Ravenclaw 
* 

3 
Slytherin 
Ravenclaw 
* 

4 
Gryffindor 
~150 
Hufflepuff 
~0 

G: §: Potter; c: Johnson, Spinnet, Bell; b: Weasley F & G; k: +Wood  
5 
Slytherin 
Hufflepuff 
* 

6 
Ravenclaw 
Gryffindor 

G: c: Johnson, Spinnet, Bell; b: Weasley F & G; k: +Wood 
Rankings: 1st, Slytherin (2 victories); 2nd, Gryffindor (2 victories, but huge loss in match 6); 3rd, (1 victory by large margin in match 6); 4th, Hufflepuff (1 victory).
Comments: Match 4 finished almost immediately thanks to Harry Potter’s very quick capture of the Golden Snitch, so that it is very likely to have been the only score. Are we really supposed to believe that among fiftyplus eligible Gryffindor students from secondyear onwards, there were no reserve players at all on standby for Match 6 (whether capable of flying on a broom or not)?
Harry Potter and the Chamber of Secrets [CS = Y12/13]
Match 
Victor 
Loser 
Reference 


1 
Gryffindor 
~150 
Slytherin 
~60 

G: §: Potter; c: Johnson, Spinnet, Bell; b: Weasley F & G; k: +Wood S: s: Malfoy; c: +Flint, Pucey; k: Bletchley 

2 
Hufflepuff v Ravenclaw 
* 

3 
Ravenclaw v Slytherin 
* 

4 
Gryffindor v Hufflepuff 
Rankings: tournament cancelled before start of play in match 4.
Comments: we assume the Slytherin Keeper Bletchley holds his position in the team during the intervening years between the first mention of him, in Philosopher’s Stone chapter 11, and again in Order of the Phoenix chapter 19. (Unless two siblings or namesakes, are both sorted into Slytherin and happen to play the same position; a similar situation could apply to the Chaser Adrian Pucey, since the Pucey in Order of the Phoenix is not referred to by first name.)
Harry Potter and the Prisoner of Azkaban [PA = Y13/14]
Match 
Victor 
Loser 
Points difference 
Reference 


1 
Hufflepuff 
Gryffindor 
100 

G: s: Potter; c: Johnson, Spinnet, Bell; b: Weasley F & G; k: +Wood H: §: +Diggory 

2 
Ravenclaw 
Hufflepuff 

3 
Slytherin 
Ravenclaw 

4 
Gryffindor 
~230 
Ravenclaw 
~30 

G: §: Potter; c: Johnson, Spinnet, Bell 1; b: Weasley F & G; k: +Wood R: s: Chang; c: +Davies 

5 
Slytherin 
Hufflepuff 
[PA9]* 

6 
Gryffindor 
230 
Slytherin 
20 
210 

G: §: Potter; c: Johnson 3, Spinnet 3, Bell 2; b: Weasley F & G; k: +Wood S: s: Malfoy; c: +Flint 1, Montague 1, Warrington; b: Derrick, Bole; k: Bletchley 
Rankings: 1st, Gryffindor (2 victories, points difference 310); 2nd, Slytherin (2 victories, points difference 280); 3rd, (1 victory); 4th, Hufflepuff (1 victory).
Slytherin’s victory in match 5 is inferred from the fact that in chapter 12 they beat narrowly, but by chapter 15 they are leading the tournament by 200 points; in chapter 9 the Weasley twins speculate that Slytherin will win this very match. The arithmetic of this implies outright aggregate points decides victory, not cumulative points difference; but compare HalfBlood Prince below. Rowling may have changed her mind on how the Hogwarts Quidditch scoring system works between the writing of these two novels – and her grasp of the arithmetic involved may still be shaky!
Harry Potter and the Goblet of Fire [GF = Y14/15]
No Quidditch matches are played as the Triwizard Tournament is held instead. It doesn’t help that the Quidditch pitch is unusable for a large portion of the year, but was there no sport played at all during the entire year? Just for the record:
Quidditch World Cup Final 


Ireland 
170 
Bulgaria 
160 

Ireland: s: Lynch; c: Troy 1 (6?), Mullet (5?), Moran 1 (6?); b: Connolly, Quigley; k: Ryan Bulgaria: §: Krum; c: Dimitrov, Levski, Ivanova 1; b: Volkov, Vulchanov; k: Zograf 
Triwizard Tournament 


Equal 1st 
Cedric Diggory Harry Potter 
Hogwarts School 
2nd 
Viktor Krum 
Durmstrang Institute 
3rd 
Fleur Delacour 
Beauxbatons Academy 
Harry Potter and the Order of the Phoenix [OP = Y15/16]
Match 
Victor 
Loser 
Points difference 
Reference 


1 
Gryffindor 
160 
Slytherin 
40 

G: §: Potter; c: +Johnson 1, Spinnet, Bell; b: Weasley F & G; k: Weasley RB S: s: Malfoy; c: +Montague, Pucey 1, Warrington 1; b: Crabbe, Goyle; k: Bletchley 

2 
Ravenclaw 
Hufflepuff 
* 

3 
Slytherin 
Ravenclaw 
* 

4 
Hufflepuff 
240 
Gryffindor 
230 
10 

G: §: Weasley GM; c: +Johnson, Spinnet, Bell; b: Kirke, Sloper; k: Weasley RB H: s: Summerby; c: +Smith 

5 
Hufflepuff 
Slytherin 

6 
Gryffindor 
Ravenclaw 

G: §: Weasley GM; c: +Johnson, Spinnet, Bell; b: Kirke, Sloper; k: Weasley RB R: s: Chang; c: +Davies 1, Bradley, Chambers 
Rankings: 1st, Gryffindor (2 victories); 2nd, Hufflepuff (2 victories); 3rd/4th, , Slytherin (1 victory each).
Harry Potter and the HalfBlood Prince [HBP = Y16/17]
Match 
Victor 
Loser 
Points difference 
Reference 


1 
Gryffindor 
250 
Slytherin 
0 
250 

G: §: +Potter; c: Robins, Thomas, Weasley GM 4; b: Coote, Peakes; k: Weasley RB S: s: Harper; c: +Urquhart 

2 
Ravenclaw 
a 
Hufflepuff 
x 
a–x 
* 
3 
Ravenclaw 
b 
Slytherin 
y 
b–y 
* 
4 
Hufflepuff 
320 
Gryffindor 
60 
260 

G: s: +Potter; c: Robins 1, Thomas, Weasley GM 1; b: Coote, Peakes; k: McLaggen H: c: +Smith, Cadwallader 2 

5 
Slytherin 
c 
Hufflepuff 
z 
c–z 
* 
6 
Gryffindor 
450 
Ravenclaw 
140 
310 

G: §: Weasley GM; c: Bell, Robins, Thomas; b: Coote, Peakes; k: Weasley RB R: s: Chang 
Rankings: 1st, Gryffindor (2 victories, points difference 300); 2nd, (2 victories, points difference 270); 3rd, Hufflepuff (1 victory, points difference –100); 4th, Slytherin (1 victory, points difference –110).
Match 4 appears to be the first Gryffindor game in seven seasons involving only one Weasley, unless Bill played on the Gryffindorteam alongside Charlie. We know from Harry’s visits to the Burrow that Bill is not only capable of playing but moreover has the inclination to do so (unlike his more conceited sibling Percy, whom it is safe to guess was probably never interested); so perhaps this is the first such match in a somewhat longer period of time to involve only a single Weasley? (I suggest the matter of Bill’s Quidditch playing would be a good open question to ask of JKR herself.)
Despite J.K. Rowling providing the reader with three match scores and the state of the rankings before the final match, there is a large discrepancy in the points difference, as at any point during the season the points difference of all four sides added together should cancel out to zero. After match 5 the results should be thus:
Team 
Points for 
Points against 
Points difference 
Inferred 

Gryffindor 
310 
320 
–10 
–10 
Ravenclaw 
a+b 
x+y 
a+b–(x+y) 
580 
Hufflepuff 
320+x+z 
60+a+c 
260+x+z–(a+c) 
–100 
Slytherin 
c+y 
250+b+z 
c+y–(250+b+z) 
–110 
Sum after match 5: 
0 
360 
It can be seen from the table when adding the points differences together that all of the unknown quantities (a, …, z) cancel out, and the sum of the known quantities is zero. This cannot be squared with the information provided by Rowling in chapter 24:
If Gryffindor beat by a margin of three hundred points […] then they would win the championship. If they won by less than three hundred points, they would come second to ; if they lost by a hundred points they would be third behind Hufflepuff and if they lost by more than a hundred, they would be in fourth place […] (HBP 24)
From this information it is evident that a winning margin counts in favour of a team, and likewise a losing margin counts against a team (presumably rather akin to goal difference in football). As Gryffindor’s points difference is –10 before the final match, at the same point ’s points difference must total 580, so that a winning margin of three hundred would increase Gryffindor’s points difference to 290 and the opposite losing margin would reduce ’s to 280. Hufflepuff and Slytherin do not gain any advantage from a Gryffindor loss in match six, so by subtraction only, Hufflepuff has –100, and Slytherin has –110 relatively. Since this sums to 360, rather than zero, therefore the points difference is considerably in error.
It would seem most likely that Rowling’s arithmetic, which she herself is the first to admit is not her strong suit, is completely fudged, or that some other unexplained rules govern the scoring of Cup points.
It should be borne in mind that if Rowling is using the system of aggregate points, then matters are no clearer! In particular, if Gryffindor lose, it should not matter by how much, since the aggregate points for is always a positive quantity and can neverdecrease. It would appear some complicated hybrid scoring system would have to be in use for this statement to make any sense.
Table of Gryffindor Players
Key:
Season: school year numbered relative to Philosopher’s Stone (PS)
HC: House Cup winner
QC: Quidditch Cup winner
Players: full names abbreviated as follows: AJ = Angelina Johnson; AK = Andrew Kirke; AS = Alicia Spinnet; BW = Bill Weasley; CM = Cormac McLaggen; CW = Charlie Weasley; DR = Demelza Robins; DT = Dean Thomas; FGW = Fred [&] George Weasley; GMW = Ginny (Ginevra Molly) Weasley; HJP = Harry (James) Potter; JP = Jimmy Peakes; JS = Jack Sloper; KB = Katie Bell; OW = Oliver Wood; RBW = Ron (Ronald Bilius) Weasley; RC = Ritchie Coote.
Other: a player’s year of schooling at Hogwarts is denoted as 1 – 7, or * if unknown. Question marks indicate a speculative guess.
Positions played: b = Beater; c = Chaser; k = Keeper; r = reserve player; s = Seeker; + denotes the team captain.
Example: the first entry for Harry Potter [HJP] reads 1s2, indicating that in his first year (1) as a student he played as a Seeker (s) in two matches (2).
Season 
HC 
QC 
BW 
CW 
OW 
AJ 
FGW 
AS 
KB 
CM 
HJP 
RBW 
DT 
GMW 
AK,JS 
JP 
RC 
DR 

PS–8 
? 
? 
1 

PS–7 
not S 
? 
2 

PS–6 
S 
G 
3 
1rs1? 

PS–5 
S 
not G 
4 
2s 

PS–4 
S 
not G 
5 
3s 
1 

PS–3 
S 
not G 
6 
4s 
2k? 

PS–2 
S 
not G 
7 
5s+ 
3k? 
1 
1 
1 

PS–1 
S 
not G 
6s1+ 
4k3+ 
2c3 
2b3 
2rc0 
1 
1 

PS 
G 
S 
[7] 
5k3+ 
3c3 
3b3 
3c3 
2c3 
2 
1s2 
1 
1 

CS (PS+1) 
G 
– 
6k1+ 
4c1 
4b1 
4c1 
3c1 
3 
2s1 
2 
2 
1 

PA (PS+2) 
G 
G 
7k3+ 
5c3 
5b3 
5c3 
4c3 
4 
3s3 
3 
3 
2 

GF (PS+3) 
? 
– 
6c0 
6b0 
6c0 
5c0 
5 
4s0 
4 
4 
3 
* 
1 

OP (PS+4) 
? 
G 
7c3+ 
7b1 
7c3 
6c3 
6 
5s1 
5k3 
5 
4s2 
b2 
2 
* 
* 

HBP (PS+5) 
? 
G 
7c1 
7rk1 
6s2+ 
6k2 
6rc3 
5cs3 
* 
3b3 
b3 
c3 

PS+6 
? 
? 
[7s+] 
[7k] 
[7c] 
[6c] 
[4b] 
[b] 
[c] 

Nº of matches played: 
JKR? 
14? 
16? 
13 
11 
10 
11 
1 
9 
5 
3 
5 
2 
3 
3 
3 
First of all note that the columns headed HC and QC, for the winners of the House Cup and Quidditch Cup in a given school year respectively, are not identical. Although Rowling herself appears to take care in distinguishing between the two, many secondary sources conflate the two competitions. The remarks in chapter 13 of Philosopher’s Stone strongly imply Slytherin won the House Cup seven years in a row prior to Harry Potter’s first year, however in chapter 17 we learn the House Cup for that year is to be the seventh (until 170 extra points decides the result in favour of Gryffindor). Thus Slytherin’s House Cup success extended for only six years in total. In chapter 8 of Prisoner of Azkaban we learn from Oliver Wood (and confirmed by Snape via McGonagall) that Gryffindor did not win the Quidditch Cup in any of the seven preceding years to that point; at best it is speculative to assign all of these as victories to Slytherin, so I have preferred to denote them as “not G”.
Regarding players: although I have omitted Gryffindors who tried out for the team but never played a match, I have included Bill Weasley in the table, on the grounds that every other Weasley played for the team, except for – of course – the selfabsorbed Percy. The shorthand describing the playing positions and number of matches is occasionally subtle: for instance, Ginny Weasley played in both Chaser and Seeker positions in HalfBlood Prince; no matches were played at Hogwarts during Goblet of Fire; the first entry for Charlie Weasley reads 1rs1?, indicating the speculative possibility that he was a reserve Seeker in his first year (I have noted this potential bending of the rules elsewhere) and played at least one match as a substitute; this appears to be the only possibility that Charlie could have played in a winning Quidditch Cup team (aside from subtle reinterpretation of various quotes taken as “evidence”).
Notes
^{[1]} Rowling’s versions of The Daily Prophet published by Bloomsbury occasionally included scores of the English Quidditch league, where the overall points accrued during the season, and not the number of victories, was the only criterion for ordering the table. There is circumstantial evidence both for and against this system also being employed at Hogwarts. To me it seems a sixmatch season would be far too short to prevent unusual results in one match from upsetting the balance of the entire year.
There are only four possible outcomes from a 4team roundrobin competition – unless there happens to be a tie in a match. (Incidentally, what does happen if a match finishes with both teams on the same number of points? Extra time without Seekers and Snitch, or perhaps a penalty shootout? The books do not tell us.) If there are no ties, then the possible cumulative results look like this:
1st 
2nd 
3rd 
4th 

3 wins 
2 wins 
1 win 
0 wins 
3 wins 
1 win 
1 win 
1 win 
2 wins 
2 wins 
2 wins 
0 wins 
2 wins 
2 wins 
1 win 
1 win 
Oddly, the results of the completed seasons featured in books 1, 3, 5, and 6 all correspond to the final row of the table. Despite this statistical oddity, half of the possible outcomes should involve a tie for first place according to the number of victories, thus necessitating some alternate method to determine the winner. Logically the points scored in the matches have to enter into consideration in some reasonable fashion.
So it is arguable that if the highest points total were the only arbiter of victory in the Quidditch Cup, then the strategy adopted by most Hogwarts teams is plainly wrong: if goals are being scored evenly by both sides then the capture of the Golden Snitch should be delayed as long as possible to allow as many goals to be scored as possible, regardless of the final outcome. In other words, a Seeker should play negatively to stymie their opposite number, while avoiding finishing the match prematurely. In this light Draco Malfoy’s occasional tactics of committing fouls on the opposition Seeker would be in keeping with the optimal strategy.
Large margins of victory may be the clinching factor, in which case we have an underlying reason for Slytherin’s presumed long dominance over the Cup: a team must win three matches to be assured of victory in the Cup, and even if a side has an incredibly talented Seeker such as Charlie Weasley or Harry Potter, negative play may prevent a victory despite the capture of the Golden Snitch. Slytherin only has to completely flatten one opponent per year to stand a chance of amassing the largest difference in points.
A final argument against awarding the Cup to the team with the highest aggregate (and this would seem to apply to other Quidditch competitions) is that it would be difficult to prevent two Seekers from agreeing to halfheartedly perform against one another, to the relative advantage of their teams as opposed to the other sides not playing.
If there is a tied match during the season, then the table of possible results becomes considerably more complicated as shown below, so it is perhaps not so surprising that J.K. Rowling hasn’t taken advantage of this quirk in the novels to date. The (even less likely) cases of more than one tie occurring during a season are left as exercises for the interested reader.
1st 
2nd 
3rd 
4th 

3 wins 
2 wins 
tie 
tie 
3 wins 
1 win, tie 
1 win, tie 
0 wins 
3 wins 
1 win, tie 
1 win 
tie 
2 wins, tie 
2 wins, tie 
1 win 
0 wins 
2 wins, tie 
2 wins 
1 win, tie 
0 wins 
2 wins, tie 
2 wins 
1 win 
tie 
2 wins, tie 
1 win, tie 
1 win 
1 win 
2 wins 
2 wins 
1 win, tie 
tie 
2 wins 
1 win, tie 
1 win, tie 
1 win 
^{[2]} Again the evidence Rowling presents is not completely free of ambiguity. Possibly Rowling conflated two possible outcomes, so that Gryffindor would go ahead of Slytherin by victories in the Quidditch Cup and by points in the House Championship.
^{[3]} Cumulative score is one possible way of differentiating the teams; but as the aggregate score in a match might vary according to the conditions on a particular day, the cumulative points difference (or, points for minus points against) would again be a fairer system.
However there are many possible ways of determining match against match scoring, and Rowling offers no conclusive evidence as to which system is in operation at Hogwarts. There is negative evidence against one possible system to resolve a twoway tie for first place (where only two teams have two victories each), which would be to decide the championship between the tied teams based on their own match result. As Gryffindor in fact defeated Slytherin in that particular match, but lose the overall championship, this method for resolving a twoway tie is evidently not in use.
^{[4]} No great influence, but some nonetheless as a team wins a match by virtue of outscoring its opponent.
^{[5]} Editor’s note: JKR has herself admitted exasperation with writing Quidditch scenes: “To be honest with you, Quidditch matches have been the bane of my life in the Harry Potter books. They are necessary in that people expect Harry to play Quidditch, but there is a limit to how many ways you can have them play Quidditch together and for something new to happen.” (TLC pt. 2)
^{[6]} In theory a student who attends Hogwarts for seven years could play a maximum of eighteen Quidditch matches. The exception made for Harry during his first year increases this number to 21, before J.K. Rowling sets about diminishing it!
Circumstances 
Number of matches 
Results 

Harry plays (9 matches) 

Harry captures the Snitch 
7 
7 wins 
The opposition Seeker captures the Snitch; 
2 
2 losses 
Harry does not play (9 matches) 

Harry is suspended 
2 
1 win, 1 loss 
Harry is in hospital 
1 
1 loss 
Harry is in detention 
1 
1 win 
The Quidditch tournament is cancelled 
5 
no result 
Harry has in fact played in only half of the possible matches he could have from his first year onward, until the end of the sixth year. Of the Gryffindor players whose careers are relatively well documented, Katie Bell played in eleven matches in the same period of time. We know Angelina Johnson played ten matches from her third year onward, and presumably played another three matches as a secondyear. Oliver Wood almost certainly played nine matches as captain after Charlie Weasley’s departure, and may have played as many as another seven if he joined the Gryffindor team as soon as he became eligible in his second year.
As for Charlie Weasley himself, I will hazard the following guess that he played fourteen matches: twelve of those in four full seasons from second to fifth year; one match as a reserve Seeker in his first year at the age of twelve, when Gryffindor won the Quidditch Cup; and his final match at the start of his sixth year. As Gryffindor did not win the Cup after his first year, it is probable that a maximum of ten of those matches can have been victories. Charlie’s win/loss ratio of about ten/four would thus be very similar to the thirteen Gryffindor matches played during Harry’s first six years at Hogwarts, resulting in nine victories and four losses.