SQL Server 2019

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CREATE TABLE t (
  ID INTEGER,
  Date_A date,
  Utility numeric
);

INSERT INTO t
  (ID, Date_A, Utility)
VALUES
  (111, '20200801', $200),
  (222, '20200701', $300);
2 rows affected

CREATE TABLE t2 (
  ID INTEGER,
  Date_B date,
  Saving numeric
);

INSERT INTO t2
  (ID, Date_B, Saving)
VALUES
  (111, '20200801', $200),
  (111, '20200701', $120),
  (222, '20200701', $900),
  (222, '20200601', $800);
4 rows affected

select *
from   t join t2 on t2.id = t.id  and datediff(month, date_b, date_a) = 1


ID
Date_A
Utility
ID
Date_B
Saving


111
2020-08-01
200
111
2020-07-01
120

222
2020-07-01
300
222
2020-06-01
800

ID	Date_A	Utility	ID	Date_B	Saving
111	2020-08-01	200	111	2020-07-01	120
222	2020-07-01	300	222	2020-06-01	800