Because 1 January is a holiday (and the weekend,) and 31 December falls on the weekend this year, the December end-of-month military payday is Friday, 30 December 2016. It should be pretty straight-forward to figure out when your 30 December 2016 military pay will be in your bank account. Most people will have their pay deposited on payday, but those who bank with military-friendly banks and credit unions may receive their deposits earlier due to the policies and/or practices of their financial institution.
USAA
USAA credits military pay one business day early as a benefit to its members, so USAA members should see their pay deposited on Thursday, 29 December 2016.
PMCU
Pacific Marine Credit Union (PMCU) credits military pay two business days prior to the actual payday, so PMCU members should see their pay deposited on Wednesday, 28 December 2016.
Service Credit Union
Service Credit Union credits military pay two business days prior to the actual paydays, so Service Credit Union members should see their pay deposited on Wednesday, 28 December 2016.
Navy Federal Credit Union
Navy Federal Credit Union (NFCU) has two different deposit dates. Members who use an Active Duty Checking account receive early direct deposit, and will see their pay deposited on Thursday, 29 December 2016. Members who use any other type of checking account, including Everyday Checking, eChecking, Flagship Checking, and Campus Checking, will see their pay deposited on Friday, 30 December 2016. (You can figure out what type of checking account you have by looking at your online account access, calling NFCU, or stopping by a branch.)
While most banks and credit unions have a time range when they "usually" deposit pay, there are no rules or guarantees about the time. When I get emails that someone's pay hasn't arrived, I usually recommend that they wait a couple of hours. 99.9% of the time, the pay gets deposited. However, if payday has ended and you still don't see a deposit, here is a list of things to do to figure out the source of the problem.