The Philadelphia Athletics have the most games by a team in a month, with 40 games in August 1938.

	TEAM	G	MONTH	W%	W	L	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	SF	IBB	GIDP	AVG	OBP	SLG	OPS
1	Athletics	40	August 1938	.375	15	25	1,404	206	399	66	21	24	202	151	4	146	15		1,586	579	111	27				.284	.355	.412	.768
2	Senators	39	August 1945	.615	24	15	1,345	177	360	55	23	12	162	143	11	107	26		1,536	497	90	37			32	.268	.343	.370	.712
3	White Sox	38	August 1938	.421	16	22	1,360	190	401	67	16	17	176	108	3	133	12		1,487	551	100	16				.295	.348	.405	.753
4	Indians	38	August 1938	.395	15	23	1,349	208	363	63	30	28	187	118	4	148	17		1,484	570	121	13				.269	.330	.423	.752
5	Pirates	38	July 1932	.658	25	13	1,369	192	404	65	21	12	175	88	9	97	10		1,492	547	98	26				.295	.342	.400	.741
6	Senators	37	August 1962	.389	14	22	1,260	141	320	49	16	30	136	90	5	201	18	15	1,381	491	95	15	11	3	30	.254	.304	.390	.693
7	Tigers	37	August 1947	.541	20	17	1,269	189	339	50	9	22	171	181	1	138	15		1,477	473	81	26			25	.267	.359	.373	.732
8	Pirates	37	August 1943	.459	17	20	1,264	150	338	65	16	13	143	113	3	157	14		1,397	474	94	17			31	.267	.329	.375	.704
9	Browns	37	August 1941	.588	20	14	1,287	182	343	61	8	21	174	189	4	118	9		1,501	483	90	21			25	.267	.362	.375	.737
10	Indians	37	September 1937	.639	23	13	1,223	173	323	71	15	26	158	130	6	120	16		1,378	502	112	19				.264	.338	.410	.748
11	White Sox	37	July 1930	.514	19	18	1,317	204	392	79	26	15	190	105	5	95	12		1,461	568	120	34				.298	.352	.431	.783
12	Yankees	37	July 1924	.622	23	14	1,291	222	383	63	18	32	201	121	5	92	21		1,460	578	113	43				.297	.359	.448	.807
13	Reds	37	September 1911	.429	15	20	1,176	132	298	29	17	2		124	12	129	81		1,349	367	48	37				.253	.331	.312	.643
14	White Sox	36	August 1968	.333	12	24	1,210	103	290	45	7	12	94	77	9	178	16	7	1,323	385	64	20	7	9	23	.240	.289	.318	.607
15	Yankees	36	August 1968	.543	19	16	1,191	98	241	32	8	23	93	132	6	223	22	10	1,351	358	63	18	4	17	19	.202	.284	.301	.585
16	Braves	36	August 1956	.600	21	14	1,167	152	306	48	6	39	141	106	5	172	11	4	1,325	483	93	39	8	15	17	.262	.324	.414	.738
17	Phillies	36	August 1953	.528	19	17	1,196	140	305	52	11	19	129	114	7	125	7	3	1,338	436	82	21			22	.255	.323	.365	.688
18	Braves	36	August 1947	.639	23	13	1,227	173	332	54	10	16	161	144	2	114	12		1,411	454	80	38			26	.271	.348	.370	.718
19	Giants	36	August 1947	.429	15	20	1,203	164	315	49	8	42	150	100	2	125	9		1,323	506	99	18			27	.262	.320	.421	.740
20	Indians	36	August 1947	.556	20	16	1,279	168	351	52	12	26	160	124	6	128	9		1,432	505	90	23			24	.274	.341	.395	.736
21	Red Sox	36	August 1945	.361	13	23	1,247	136	305	47	12	11	125	125	5	136	16		1,401	409	70	24			31	.245	.316	.328	.644
22	Giants	36	August 1941	.417	15	21	1,229	148	326	57	6	26	136	95	12	122	9		1,359	473	89	23			25	.265	.324	.385	.709
23	Dodgers	36	September 1939	.639	23	13	1,204	185	337	61	13	22	171	134	9	117	11		1,376	490	96	29			27	.280	.356	.407	.763
24	Yankees	36	August 1938	.778	28	8	1,267	275	349	65	20	51	261	219	10	154	23		1,511	607	136	15				.275	.386	.479	.865
25	Pirates	36	September 1916	.294	10	24	1,156	93	273	40	19	5	78	80	12	138	40		1,273	366	64	25				.236	.292	.317	.609