If the check is issued to us jointly, do both of us have to endorse it to deposit to a joint account? IRS issued a refund check although I clearly marked to apply it to next year’s tax.
No.
Thank you. Good to know!
No.
ETA: Oops, apparently I had this tab open a lot longer than I thought. I second ally 
You can send the $ back as a quarterly deposit if you need to.
Yes, both of you! See Banks Have Tough Rules on Check Deposits Written to More Than One Person | MyBankTracker
It is written to John & Jane. We file the tax jointly and the refund was sent us both. It’s going into a joint account.
How do I do that?
“For Deposit Only”. Yes you may. Write this on the back of the check.
@Iglooo Sorry, I meant you can deposit and send a new check as a quarterly.
Technically, you can return the check and have the IRS fix this by putting the $ in the next year’s account, but I don’t recommend that. I’ve had quite bad luck with that process (if the $ is big enough and will cause a huge penalty though if not rolled over, you may need to send it back with a letter indicating that you opted for rollover, showing that on your return. Once you cash it, the check you send back is considered new $ and can be “late”.)
I have a joint account with Mr R at one of those banks in 4kids’ link. We’ve never co-endorsed a check that was written to both of us and we’ve never had an issue.
But I guess to be safe, both parties should sign.
Frankly, you could scribble “boogers” on the back and it would not be rejected. When depositing, banks aren’t as rigid as cashing a check for cash:)
Really. Don’t we all know how to forge our spouse’s signature for stuff like this? Sheesh.
No, my wife’s signature is so unique that I don’t attempt to copy it.
I usually write “Deposit to account number”. Our bank is very strict, however, about not accepting checks NOT originally made out to one of us. Other banks are more lenient on that.
I realize this situation is a different situation, however my daughter and her two roommates received a security deposit refund check from their landlord issued to daughter, roommate 1 “AND” roommate 2. All three of them endorsed the check, but Wells Fargo (2 of them have separate accounts there) would not allow my daughter to deposit the check unless all three payees were present… which has not happened since one of them graduated and lives 2 states away. It took 3 months to get her to endorse the check and there has not been a time in which the 3 have been together during banking hours. This has been a real PITA!
I would think there would be less potential for a hassle of you both sign the check, unless there is a reason that can’t be done. You could always call your bank and ask.
Ha! @Pizzagirl I was going to say the same thing. I sign my wife’s name to be ‘safe’…never had a problem. Actually, I was once told I could legally sign for my wife. It sounded good to me, so I went with it. Never, ever, an issue with deposits. I wouldn’t try it when cashing a check, however.
@HRSMom That’s a good point sending new money will be “late” They may charge me penalty. It would make financial sense to send the check back to rollover if I can trust IRS works efficiently. Far from it. It took them 7 months to resolve a minor issue and send a refund check. I bet it will take them 7 months to receive the check if I return it. It may end up cheap to just pay the penalty than deal with IRS.
DH laughs that if he ever really tried to sign anything they would reject it since it would not look like the way I sign his name 
You are right. I had an issue where the check went back, they resent, issued a penalty. Returned check again, same result. Ultimately I had to hire someone to deal with it as it was too time consuming and needed someone with connections to make sure it got fixed. Such a pain.
That link included this caveat: if you don’t share an account with this other person. Spouses can usually deposit to a joint account.
The issue isn’t that you’re breaking some “rule” up front, when it’s a spouse and a joint account. It’s if there is some contest later, which, afaik, isn’t likely between spouses, who routinely represent each other in various accepted ways. The IRS isn’t going to check all their processed checks and come after you. If you deposit at the ATM, no teller. But no, I wouldn’t deposit a check I shared with a third party, to my own personal account. That’s another matter. The other would need to sign it over to you.
I like using my local branch and them knowing us. It has worked well for us.