My mother is moving to Washington State from Dallas Texas. Does she have to go to SSA office to get changed of address and apply for Wa State SSA benefits? Does she get it the very next month, or does it delay her benefit?

SSA is a federal entity and SSD & SSI benefits are federal programs. Moving states has no effect on them. So all she has to do is file an address change. It can be done at her new local office or online. I wouldn't recommend calling in. Even on the best of days their phone systems have hrs long wait times and no guarantee you'll reach someone able to help w/your specific issue. It's unlikely there will be any delay in her benefits, as most ppl recieve them as a direct deposit to their bank account, and not an actual mailed check.

She will continue to get her SS benefits. She doesn't need to reapply. But she needs to notify SSA of her new address. Probably should call the main SSA number plus notify the previous office to make sure address change is reflected accurately

Check website first...SSA.gov