[iMore Question]

I want to use an iPhone 6sPluse on a prepaid service. Namely Metro PCS, or possibly Boost Mobile

[Sherry_B]

It's a GSM network, so you should be able to take an unlocked phone that supports the band(s) T-Mobile uses. Since Metro PCS is owned by T-Mobile you will be using the T-Mobile network.

[Highrisedrifter]

Yes you can take an unlocked phone to another service. You'd have to check specifically with Boost or Metro PCS but I did it with AT&T a year back. Many carriers are divorcing themselves from the old bundles of wrapping the phone up with the monthly contract and opting for separate (usually higher) costs for each, meaning you have the option to just get a contract for the service, without getting the phone too.