The Boston Red Sox had the best on-base percentage by a team in 2004, with an on-base percentage of .360.

	TEAM	OBP	SEASON	G	W%	W	L	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	SF	IBB	GIDP	AVG	SLG	OPS
1	Red Sox	.360	2004	162	.605	98	64	5,720	949	1,613	373	25	222	912	659	69	1,189	68	30	6,515	2,702	620	12	55	39	123	.282	.472	.832
2	Giants	.357	2004	162	.562	91	71	5,546	850	1,500	314	33	183	805	705	72	874	43	23	6,466	2,429	530	92	51	153	142	.270	.438	.795
3	Yankees	.353	2004	162	.623	101	61	5,527	897	1,483	281	20	242	863	670	80	982	84	33	6,364	2,530	543	37	50	40	157	.268	.458	.811
4	Indians	.351	2004	162	.494	80	82	5,676	858	1,565	345	29	184	820	606	78	1,009	94	55	6,449	2,520	558	47	42	41	143	.276	.444	.795
5	Phillies	.345	2004	162	.531	86	76	5,643	840	1,505	303	23	215	802	645	58	1,133	100	27	6,456	2,499	541	64	46	60	123	.267	.443	.788
6	Rockies	.345	2004	162	.420	68	94	5,577	833	1,531	331	34	202	795	568	54	1,181	44	33	6,333	2,536	567	97	37	51	132	.275	.455	.800
7	Orioles	.345	2004	162	.481	78	84	5,736	842	1,614	319	18	169	803	528	57	949	101	41	6,429	2,476	506	46	62	34	126	.281	.432	.776
8	Cardinals	.344	2004	162	.648	105	57	5,555	855	1,544	319	24	214	817	548	51	1,085	111	47	6,297	2,553	557	73	70	64	121	.278	.460	.804
9	Athletics	.343	2004	162	.562	91	71	5,728	793	1,545	336	15	189	752	608	55	1,061	47	22	6,459	2,478	540	25	43	40	142	.270	.433	.776
10	Braves	.343	2004	162	.593	96	66	5,570	803	1,503	304	37	178	767	587	59	1,158	86	32	6,339	2,415	519	75	48	51	123	.270	.434	.777
11	Padres	.342	2004	162	.537	87	75	5,573	768	1,521	304	32	139	722	566	56	910	52	25	6,313	2,306	475	52	66	45	128	.273	.414	.756
12	Astros	.342	2004	162	.568	92	70	5,468	803	1,458	294	36	187	756	590	61	999	89	30	6,269	2,385	517	98	52	54	128	.267	.436	.778
13	Angels	.341	2004	162	.568	92	70	5,675	836	1,603	272	37	162	783	450	73	942	143	46	6,295	2,435	471	56	41	43	123	.282	.429	.770
14	Tigers	.337	2004	162	.444	72	90	5,623	827	1,531	284	54	201	800	518	50	1,144	86	50	6,284	2,526	539	50	43	32	110	.272	.449	.786
15	White Sox	.333	2004	162	.512	83	79	5,534	865	1,481	284	19	242	823	499	63	1,030	78	51	6,196	2,529	545	58	42	25	119	.268	.457	.790
16	Twins	.332	2004	162	.568	92	70	5,623	780	1,494	310	24	191	735	513	64	982	116	46	6,286	2,425	525	46	40	42	130	.266	.431	.763
17	Dodgers	.332	2004	162	.574	93	69	5,542	761	1,450	226	30	203	731	536	62	1,092	102	41	6,244	2,345	459	69	35	45	121	.262	.423	.755
18	Reds	.331	2004	162	.469	76	86	5,518	750	1,380	287	28	194	713	599	81	1,335	77	25	6,278	2,305	509	55	25	38	125	.250	.418	.749
19	Mariners	.331	2004	162	.389	63	99	5,722	698	1,544	276	20	136	658	492	54	1,058	110	42	6,362	2,268	432	46	48	49	131	.270	.396	.727
20	Marlins	.329	2004	162	.512	83	79	5,486	718	1,447	275	32	148	677	499	58	968	96	43	6,160	2,230	455	77	40	37	142	.264	.406	.736
21	Rangers	.329	2004	162	.549	89	73	5,615	860	1,492	323	34	227	825	500	61	1,099	69	36	6,256	2,564	584	23	57	41	91	.266	.457	.786
22	Blue Jays	.328	2004	161	.416	67	94	5,531	719	1,438	290	34	145	680	513	71	1,083	58	31	6,177	2,231	469	20	42	25	139	.260	.403	.732
23	Cubs	.328	2004	162	.549	89	73	5,628	789	1,508	308	29	235	755	489	38	1,080	66	28	6,281	2,579	572	78	48	46	120	.268	.458	.786
24	Royals	.322	2004	162	.358	58	104	5,538	720	1,432	261	29	150	675	461	76	1,057	67	48	6,153	2,201	440	40	38	28	130	.259	.397	.720
25	Pirates	.321	2004	161	.447	72	89	5,483	680	1,428	267	39	142	648	415	95	1,066	63	40	6,114	2,199	448	79	42	33	117	.260	.401	.722