It's not unusual for a check to be written out to just one spouse. A paycheck would be made out to only the employee, not the employee and their significant other. This doesn't mean that Spouse A, who earned the money, can't endorse the check and give it to Spouse B to deposit at the bank.
There's a catch, however. That paycheck belongs to both of them as soon as it lands in an account that they jointly hold.
How a Joint Account Works
Two individuals who are co-owners of a joint account don't each own 50 percent of the money there. They each have an equal right to all the funds that are held in the account. This would be the case even if they weren't married. It doesn't matter where the deposits came from, what they were for or to whom the checks were written. Either co-owner can empty the account without the consent – or even the knowledge – of the other.
This also means that a disgruntled creditor of just one of the co-owners can sue that person for payment, get a judgment and use the judgment to collect a debt from the joint account. The co-owner would have no rights in this situation even if they didn't also owe the debt in question because the two individuals own the account equally.
How to Deposit a Check to a Joint Account
Not only can you deposit a check to just one spouse into a joint account, but you have a few options for doing so. The first would be that Spouse A simply endorses the check and someone – Spouse B or any other party – can take it to the bank. The bank will accept the check because Spouse A is an equal owner on the account into which the check is being deposited.
But what if Spouse A isn't available to endorse the check? That's okay, too. Spouse B can simply write "For Deposit Only" on the back of the check where Spouse A would normally have signed it. Again, all Spouse B is doing is depositing Spouse A's money into an account that Spouse A owns. The funds are going to the rightful recipient.
Making a Third-Party Transaction
You also have the option of making a third-party transaction, but this would complicate an otherwise very basic situation and it would be unnecessary if the account into which the money is being deposited is jointly held. A third-party transaction effectively involves signing the check over to someone other than Spouse A, who is the rightful payee.
Spouse A would sign the check in this case and write "Pay to the order of…" and someone else's name right beneath their signature. The check has now been written over to someone else, whether it's Spouse B or Joe Neighbor. That individual can now endorse the check just as though it had been written out to them personally and deposit it in any account they like. They could even cash it.
It Can Depend on the Paying Bank
Not all banks are willing to accept third-party checks, and it's possible that the paying bank won't honor a check that's deposited this way. The receiving bank will send the check to the paying bank at the end of the business day, and the paying bank would then have the option to approve the endorsement or decline it.
It's far simpler for Spouse A to simply endorse the check and hand it over to Spouse B if Spouse A can't personally take it to the bank. The bank should have absolutely no problem with that, given that both Spouse A and Spouse B have an equal, total right to the account.