Add 1 year to todays date.

DATEADD(YEAR, 1, GETDATE())

Subtract 1 year from todays date.

DATEADD(YEAR, -1, GETDATE())

Add 1 month to todays date.

DATEADD(MONTH, 1, GETDATE())

Add 5 days to todays date.

DATEADD(DAY, 5, GETDATE())

Add 1 year to a specific date.

DATEADD(YEAR, 1, '2017-01-01')

Possible increments.

year quarter month dayofyear day week weekday hour minute second millisecond microsecond nanosecond