If you already have a TMobile plan you can switch out the sim if it fits.

Thanks gramps28.  Yes, I have an existing tmo plan, just an old phone (with a micro sim) so as long as the new tmo branded prepaid phone at walmart takes a micro sim, I should be okay.  Thanks again.  I didn’t know if the phone intended for a prepaid plan was somehow locked into a prepaid plan activation or something.

Yep you should be fine. If it's a 5G phone you may want to get a new sim down the road.

Okay, yes it is a 5G phone so thanks for the recommendation on a new sim card.  I’m thinking one might come with the new phone since it’s a TMO branded prepaid phone.  Thanks!

On a side question, would a “Metro by TMO” prepaid phone work on my TMO plan?  Or would I first have to get it “unlocked”?  

Little delayed answer to the metro question. You would first have to get the phone for metro unlocked to use it for T-mobile.

I need a cheap travel phone that will work with my T-Mobile plan. Any ideas will be appreciated.