When to contact re:late rent

[Alan Berlin]

I've had the same tenant for about 2 years.  Usually he pays rent a couple of days early and  he has never been late.  Its the 2nd of the month and he hasn't paid yet. At what point should I contact him to check in? Rent is due on the 1st but late fees kick in if he hasn't paid by the 5th.  Should I contact him now (on the 2nd) or wait until the fifth? 

Thank you,

Alan