Good Afternoon,

I am not sure if The Pensions Regulator (TPR) deals with just business or the general public as well, so that maybe why they only have an 0845 number.  Anyway, I took a look on the Pension Regulator website, and found their address which is in Brighton.  Napier House is the 1st part of the address.

I searched for The Pensions Regulator Napier House and just got the usual 0845 number, then tried with 01273 (the dialling code for Brighton) and got several useful results.

One lists a number of Solicitors at TPR Napier House, but ALL have the same contact number which suggests it's reception.  I would therefore suggest you try 01273 627600 and let us know how you get on.

I have not called it today, as it's a Sunday.

Update:
Tried 01273 627600, only to find it similar to 811800, in that it only has a recorded announcement directing callers to the 0845- numbers.
Also tried -648400, hoping it might be a reception/switchboard, but without luck again, this appearing to be some access number to an Avaya voice messaging system which, despite announcing assistance may be had by entering "Oh" = (unclear whether 0[zero] or O [letter O]), then informs either selection is invalid & suggests trying later before disconnecting the call...
In the end I contacted a number (-662086) found for the press office, who did arrange for someone to call me back.
Should I ever happen upon a geographic switchboard number, I'll make a point of listing it on this site, but have for now stopped looking and, given the degree of difficulty, am not optimistic of coming across one any time soon.
Once again, thanks for helping.