On ADSL Talk Talk offer SMPF services so you can have your phone line with one provider (say BT) and your broadband with Talk Talk. However ive yet to see a provider offer this on Fibre.
Plusnet do not insist on phone being with them on FTTC. Nor it seems to BT Consumer, despite the fact they only advertise packages that require it. It is in their current Price Guide.
AAISP allow SMPF, in fact if you want a line to make non-VOIP calls on it is all they offer. They don't offer a retail PSTN service.
Many of the smaller companies offer SMPF.
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