Will I serve any US sentence in a British prison under a prisoner transfer agreement?

The UK and US are both parties to the Council of Europe Convention on the Transfer of Sentenced Persons, which theoretically permits repatriation. In practice, transfers from US federal custody to UK prisons are rare and discretionary — the US Bureau of Prisons must consent, and applications typically require serving a substantial portion of the sentence first. Federal sentences also carry different release structures than UK sentences, and time served calculations can be unfavourable. Transfer should never be relied upon as a defence strategy; it is a post-conviction possibility with no guarantees.