Without any unlock code?
Welcome to Android Forums. Yes, it should - the phone is not carrier-locked to Verizon - but, with a few caveats:
- I have read that the phone needs to be previously activated on a Verizon network before the GSM bands are unlocked. I'm not sure if or why that is true, but I've read a few posts on xda-developers.com from people who have purchased phones never activated on Verizon who cannot get them to work on other networks. If you purchase this phone new and do not activate it on a Verizon plan first, it may not work on AT&T later.
- LTE will probably not work, but you should get HSPA+ on AT&T. I've read that the phone has issues switching from LTE to HSPA+ or HSPA on T-Mobile, so that may be a good thing.
- saying all that, this phone was designed to be used on Verizon networks. The GSM bands are there for Verizon customers to use internationally. The SIM slot is not carrier-locked to Verizon, so an AT&T nano SIM *should* work, but don't be surprised if there are issues going forward.
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