When do you start using your new name?

You can use it socially right away, but until you receive your new social security card and license, I wouldn't use it for work or legal purposes.

I would say just start tackling one thing at a time. There is no need to wait, but there is also no need to stress about getting everything all done at once. You can start changing it anywhere that is not legal and introducing it as soon as you are married. There will be some things where they need if official first: payroll, credit cards, drivers licenses, etc. For those, you will have to wait until you get your new SSN card.

I waited until I had my social and license updated to let HR know. I also brought them nt marriage license as proof.

I signed my new name on our thank you cards and use it socially with our friends. But I have not changed it on my work email signature because it is not my legal name yet. I will wait until I get my new SS card and it is a legal name change before I make any changes like an email signature, notifying HR, or introducing myself in a professional capacity.

I second PPs! You can go ahead and start using your new last name informally The legal part might take a little while, but I see no issue in introducing yourself with your new name!

I waited until I filed paperwork for new Social Security Card & Driver's License. Which my HR instructed me to do. I did change my email signature right away & my voicemail.

I started using it right away, I changed my work email & business card just before the wedding then right after I did the social security card, driver's license & credit cards/bank accounts. Then once those were done, I moved to easier things like voter registration, car insurance, etc.

I think changing a work email and signature is no problem. That's not really tied to anything legally. Changing tax information, retirement, etc when the social security isn't changed might be an issue.

At work and socially you can change immediately with everything but payroll. When you change So Sec name, then the next payroll and retirement stuff should be in the same as new name. You can let them know at that time if you want one W2 to end at marriage, new to begin. Or just have the same til the following January. If your finances and taxes were separate til you married, then went joint, you want separate ones. And new withholding on file. If you filed as one household, or business and property together before, check to see about new withholding etc. Other than legal papers, you can use any name you want, whenever you want, as long as you are not deliberately misleading someone, or attempting to defraud them. If you want to fly, get your new Real ID license fast.

I started using my new name informally/legally right away. I didn't start using my new name legally until after I had gone to the social security office & DMV. I changed my bank account info right away (only needed marriage certificate at my credit union), and credit cards. Everything else including my work, I had to wait to receive my new social security card and driver's license. It took me about a month to get everything changed (a lot of waiting around for documents to change), I haven't changed my passport yet