Send T-mobile my old phone for them to pay ETF?

I'm thinking of switching to t-mobile and having them pay my Sprint ETF, but I don't want to send them my phone. Can I just send them an old phone?

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› See More: Send T-mobile my old phone for them to pay ETF?

As long as the phone works, yes. T-mobile has no way of knowing whether the phone was active on your account. Though I wouldn't send them a phone from another carrier other then the one you're currently on.

Just some clarification - if the phone was reported lost or stolen they will not give you credit for it.