Sammy Sosa has crushed the most home runs in the NL in a month, with 20 home runs in June 1998.

	NAME	HR	MONTH	G	AB	R	H	2B	3B	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	SF	IBB	GIDP	AVG	OBP	SLG	OPS
1	Sammy Sosa S. Sosa	20	June 1998	27	114	25	34	2	0	40	6	0	27	0	2	121	96	22	0	1	0	3	.298	.331	.842	1.173
2	Giancarlo Stanton G. Stanton	18	August 2017	29	109	28	38	6	0	37	14	3	31	1	0	127	98	24	0	1	4	2	.349	.433	.899	1.332
3	Sammy Sosa S. Sosa	17	August 2001	29	109	31	42	3	3	36	16	3	24	0	1	130	102	23	0	2	3	0	.385	.469	.936	1.405
4	Barry Bonds B. Bonds	17	May 2001	27	84	28	31	5	0	30	31	2	24	3	1	117	87	22	0	0	5	1	.369	.547	1.036	1.583
5	Willie Mays W. Mays	17	August 1965	31	113	32	41	3	0	29	17	0	19	1	1	131	95	20	1	0	3	1	.363	.446	.841	1.287
6	Kyle Schwarber K. Schwarber	16	June 2021	27	100	22	28	0	0	30	13	1	33	0	0	116	76	16	0	2	0	3	.280	.362	.760	1.122
7	J.D. Martinez	16	September 2017	24	99	26	40	8	0	36	7	0	29	1	0	107	96	24	0	1	1	7	.404	.439	.970	1.409
8	Mark McGwire M. McGwire	16	July 1999	25	88	21	26	2	0	30	22	0	21	0	0	110	76	18	0	0	4	0	.295	.436	.864	1.300
9	Mark McGwire M. McGwire	16	May 1998	26	86	25	28	2	0	32	33	0	27	0	0	119	78	18	0	0	5	0	.326	.513	.907	1.420
10	Ralph Kiner R. Kiner	16	September 1949	27	92	28	30	4	1	32	28	0	10	2		120	84	21	0			4	.326	.483	.913	1.396
11	Shohei Ohtani S. Ohtani	15	May 2025	27	110	31	34	5	1	27	17	0	31	2	3	128	86	21	0	1	5	2	.309	.398	.782	1.180
12	Troy Tulowitzki T. Tulowitzki	15	September 2010	28	115	30	37	6	2	40	9	1	19	2	0	125	92	23	0	0	1	3	.322	.376	.800	1.176
13	Jim Thome J. Thome	15	June 2004	27	98	25	30	5	0	31	21	1	25	0	0	121	80	20	0	1	6	1	.306	.430	.816	1.246
14	Sammy Sosa S. Sosa	15	August 1999	30	109	20	31	2	0	28	20	1	36	1	3	130	78	17	0	0	4	4	.284	.400	.716	1.116
15	Mark McGwire M. McGwire	15	September 1998	25	82	24	27	2	0	28	19	1	24	0	0	102	74	17	0	0	1	1	.329	.461	.902	1.363
16	Mark McGwire M. McGwire	15	September 1997	26	98	21	28	1	0	24	20	2	36	1	0	121	74	16	0	1	5	0	.286	.413	.755	1.168
17	Andre Dawson A. Dawson	15	August 1987	27	110	23	34	2	0	28	9	0	16	2	2	119	81	17	0	0	2	4	.309	.361	.736	1.098
18	Pedro Guerrero P. Guerrero	15	June 1985	25	93	27	32	3	0	26	15	1	14	2	0	110	80	18	0	1	3	2	.344	.436	.860	1.297
19	Joe Adcock J. Adcock	15	July 1956	31	95	21	34	5	0	36	11	1	16	0	0	110	84	20	3	0	3	2	.358	.430	.884	1.314
20	Duke Snider D. Snider	15	August 1953	31	127	30	44	7	0	41	12	1	22	0	2	141	96	22	1			1	.346	.407	.756	1.163
21	Cy Williams C. Williams	15	May 1923	30	124	29	44	8	0	44	17	1	9	5		142	97	23	0				.355	.437	.782	1.219
22	Aristides Aquino A. Aquino	14	August 2019	29	103	22	33	4	0	33	10	2	26	2	0	115	79	18	0	0	2	4	.320	.391	.767	1.158
23	Albert Pujols A. Pujols	14	June 2009	29	97	19	31	10	0	35	19	0	14	2	1	117	83	24	0	1	8	4	.320	.427	.856	1.283
24	Alfonso Soriano A. Soriano	14	September 2007	28	122	22	39	11	0	27	6	1	31	1	1	130	92	25	0	1	0	1	.320	.354	.754	1.108
25	Ryan Howard R. Howard	14	August 2006	29	112	25	39	3	0	41	22	3	33	0	0	138	84	17	0	1	10	1	.348	.464	.750	1.214