SQL Server accuracy of milliseconds is 1/300th of a second and the possible values are .000, .003 and .007. Any datetime value in SQL Server with milliseconds will be rounded to one the nearest of these three values.

The table lists all possible last digit of millisecond

 

Original/Import millisecond

SQL Server Millisecond

Difference

.000

.000

0

.001

.000

-1

.002

.003

+1

.003

.003

0

.004

.003

-1

.005

.007

+2

.006

.007

+1

.007

.007

0

.008

.007

-1

.009

.010

+1

 

Whilst you compare values, SQL Server interprets milliseconds the same way i.e., it converts the value to SQL Server compabile and compares it, hence, No issue if the values are compared within SQL Server.