If I change my gamertag on the web, will the new gamertag be seen consoles as well?

Hi and thanks for reaching Microsoft Xbox gamer's community. My name is Josef.
I'm an Independent Advisor and a Microsoft Xbox user like you.

Hope you're doing great today Danny Patrick

Yes, the change is reflected everywhere

But keep in mind that two gamertag systems exists. When you change it, depending on the chosen gamertag you can see a suffix next to the name.

Some games doesn't support the new gamertag system. So they're going to use the gamertag with the suffix

If I change my gamertag, will that gamertag go back into the pool for usable gamertags for other users?

Yes it will but it takes years from what ive seen and with the new system it might be faster

Hi Steven!

Did you change your gamertag through the console or through the web https://social.xbox.com/ChangeGamerTag?

What gamertag is showing on https://account.xbox.com/Settings? Is it the new one or the old one?

When you play your games on your Xbox, does it show your new gamertag?
Which section or page you see the old one?

I'm getting error code 80151006. This happened when I changed my gamertag on my new 360. My old gamertag and profile downloaded just fine on the new console but now that I changed it I can't download it. I've also tried to download my profile with my new
gamertag on my old console, it also will not download and I get the same error code.

Well, I've seen this happened before, it shows two gamertags. But this happened (in the case I once saw) after a change from ine gamertag to another, like some kind of glitch that held the former gamertag and alse the new one! Don't know exactly why it happens. I'm looking into it right now to see if I come across any possible fix.