Deadline to credit contributions to service provider's account?

Is there a legal deadline by which employer contributions (such as matching contributions) must be credited to a participant's account under a nonqualified plan governed by 409A?

One template I've seen provides a deadline for crediting of matching contributions of "as soon as practicable following the last day of the Plan Year to which the Matching Contribution relates and in no event later than the March 15 immediately following the Plan Year." Is March 15 just a random, reasonable date, or is it somehow tied to the short-term deferral rule (probably totally off base there)?

Trying to understand the legal limits involved here. Thank you!

For example, if the employer didn't want to calculate and credit matching contributions until June of the following year (with CY PY), would that run afoul of 409A?

Beyond tax law:

A deferred compensation plan is a contract between the employer or service recipient and the employee or nonemployee service provider.

If that contract specifies when an amount is credited to an obligee’s account, the employer ought to follow the obligation the employer made.

If the relevant document is not specific, the obligor ought to act in good faith, with fair dealing, and reasonably so as not to deprive the obligee of the benefit of the parties’ bargain.

This is not advice to anyone.

Agreed, it should have been spelled out in either the plan, an underlying employment agreement, or both - if well-designed. Otherwise, you're in the good-faith/fair-dealing gray area. If some sort of supplement to a qualified salary deferral/match arrangement then adhering to that practice or statutory timing could be deemed reasonable.

And, as Peter notes, this is not advice to anyone.

409A is extremely complicated.  There generally aren't requirements about when benefits accrue or are credited--409A is generally focused on hard and fast rules for the time and form of payment.  That said, though, sometimes the two can be tied together by design... so the answer is going to be very fact intensive and can only be answered for a given plan by reviewing the document. 

Are you drafting the plan and asking if you can meet the service recipient's desires regarding that timing or has the plan already been executed and it is silent on this issue (now the service recipient wants to "credit" the amounts on 6/1)?  Also, when you use the word "credited" do you mean accrued in their notional account on the books/ledger?

All the posters above are correct that this is a contractual issue and the application of 409A is complicated. 

Having said that, here are my ramblings.  Regarding the language used in your specimen document, I agree it seems that it is using short-term deferral type of language.  To me this is an overly conservative use of that language as that timing only comes in with distributions and not with accruals.  The specimen document must either provide or the quoted provision assumes that the service provider has a legally binding right to the match on 12/31/yr1.   If that is the case though, it doesn't seem like it should matter when the accrual is actually being made because legally speaking the amount that should be accrued would be set as of 12/31/yr1.   That is, even if the service recipient waits until 3/15/yr2 to accrue and the service provider terminates on 2/1/yr2 (assuming no other vesting provision), the service provider still would need to be credited with the amount of the match as of 12/31/yr1.   Ultimately, it seems like it wouldn't matter when it is actually credited on the books as long as the service provider can calculate the amount owed to the service provider when a distribution is due.  The problem with delaying would be that the calculation of earnings is more difficult (unless there is a fixed earnings rate). 

Of course, the plan document could be drafted such that the service provider does not have a legally binding right to the match until 6/1/yr2 (a type of tin handcuff) so they do not have to credit it until that date (if this is done you should make it clear whether this credit is retroactive to 12/31/yr1 or treated prospectively).  Could this be what the service recipient is seeking?

Even if this is not a pure notional account but amounts are to be contributed to a rabbi trust, then a delay would be a contractual issue between the service provider(s) and the service recipient and not a tax issue.

Reiterating everyone else... not advice.