Gofynnodd Christopher S. gwestiwn i HR Community
I Joined HMC&E in 1968 and spent the bulk of my time in uniform, from HM Waterguard to my retirement from HMRC as a Detection Senior Officer in June 2007. I was under the impression that my Civil Service Pension included the ‘uniform Addition’, but it does not. MyCSP are as useful as a chocolate teapot and their reputation for getting things wrong, being slow, inefficient and indifferent is justified. After many months waiting for an answer from them, they came back with the “nothing to do with us” excuse and referred me to HMRC. MyCSP did not provide any contact details and I cannot find any on the HMRC web pages. Any suggestions gratefully received!
Hi, I'm afraid we aren't able to answer enquiries such as this on this platform, we would direct you to MyCSP as they deal with the pension. I've had a search not sure if this would be useful, Help trace old pension scheme detail 0800 731 0193 or contact HR Unity Business Services, Operations, HMRC 
Teville Gate House
Newcastle
NE98 1ZZ
Thank you for your reply.
I accept that this is not proper to this platform, but there is no 'general HMRC' switchboard number, hence my accessing this platform in the hope you would be able to provide a name and/or a contact number.
The number you have provided is for private pensions, not Civil Service.
As I pointed out in my post, I have already contacted MyCSP about this, and they directed me back to HMRC.
I will try your HR Unity Business Services as you suggest, but I am not confident they will be able or willing to get involved. I will wait and see, but there will likely come a point where I will have to go to my MP and ask him to get involved.

Mae’r wefan hon yn defnyddio cwcis.
Rydym yn defnyddio cwcis i bersonoli cynnwys fel argymhellion swyddi, ac i ddadansoddi ein traffig. Rydych yn cydsynio i’n cwcis os ydych yn clicio "Rwy’n Derbyn". Os byddwch yn clicio ar "Nid wyf yn derbyn", yna ni fyddwn yn defnyddio cwcis ond efallai y bydd gennych brofiad defnyddiwr dirywio. Gallwch newid eich gosodiadau trwy glicio ar y cysylltiad Gosodiadau ar frig y ddyfais
Mae’r cwcis hyn yn angenrheidiol er mwyn i’r wefan weithredu ac ni ellir eu diffodd yn ein systemau. Fel arfer, dim ond mewn ymateb i gamau a wnaed gennych sy’n gyfystyr â chais am wasanaethau, megis gosod eich dewisiadau preifatrwydd, mewngofnodi neu lenwi ffurflenni. Gallwch osod eich porwr i’ch rhwystro neu eich rhybuddio am y cwcis hyn, ond ni fydd rhai rhannau o’r wefan yn gweithio wedyn.
Mae’r cwcis hyn yn ein galluogi i gyfrif ymweliadau a ffynonellau traffig fel y gallwn fesur a gwella perfformiad ein gwefan. Maen nhw’n ein helpu ni i wybod pa dudalennau sydd fwyaf a lleiaf poblogaidd a gweld sut mae ymwelwyr yn symud o gwmpas y wefan. Os na fyddwch yn caniatáu’r cwcis hyn, ni fyddwn yn gwybod pryd rydych wedi ymweld â’n gwefan, ac ni fyddwn yn gallu monitro ei berfformiad.