Yes — every sleeper coach has toilet facilities, but whether you get your own en-suite depends on the room you book. On the Caledonian Sleeper, the two top grades — the Club En-suite Room and the Caledonian Double — each have a private en-suite with a toilet and shower. The cheaper Classic Room does not have its own toilet; it has a washbasin in the room, and you use the shared toilets in the coach corridor. Guests in reclining Seats also use the toilets provided in the seated coach. So there's always a toilet available, but a private one is a feature of the en-suite rooms only. On the GWR Night Riviera to Cornwall, cabins have a washbasin but no en-suite toilet or shower — you use the toilets in the coach and the shower facilities in the First Class lounges at Paddington, Truro and Penzance. In short: toilets are always accessible on both services; en-suite facilities are limited to the Club and Caledonian Double rooms on the Scottish sleeper. If a private bathroom matters to you overnight, book one of those en-suite grades.
Sources: sleeper.scot · gwr.com
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