New gas combi boiler, radiators installed and new sockets and spotlights but no certificates

You should have received some sort of certification (ie, Electrical Installation Certificate or Minor Electrical Works Certificate) depending on what works were carried out. Again depending on the works and location of works (Bathroom Zoning) the local authority (council) should of been notified if required for notification as not all electrical works are notifiable. I would also recommend that you don't use an electrician purely based on the governing body in which they pay for...a logo doesn't define the electricians skills or how trustworthy they are! NICEIC / NAPIT / BSI / ELECSA / ECA - unfortunately the scheme providers aren't at a position were they are willing work together to create a one for all "safe scheme" for the consumer.

Ok 100% yes you should have certification under building control legislation, it is a requirement that all electrical and gas work needs to be certified and notified to building control. If I were you I would contact the companies who carried the works out via email so it is logged requesting them politely and also call them in person as a gentle reminder requesting them. If no joy then check with their governing bodies i.e gas safe & NICEIC for example to check that the company or companies you used are actually registered and compliant and if they are, then they should supply you with the relevant documents. If not, I would strongly advise you get the work tested and certified by recommended electrical and gas installers to ensure its safety. I recommend you use the gas safe website and NICEIC website to source local trust worthy engineers, you will also be able to look up the companies who done your previous works if they are actually registered at all!? I really hope this helps and it works out for you. Best wishes, Jon (JEM EBS Ltd)

Unless certificates for the electrical works were issued and the completed job notified to building control then the work has been done illegally and you as the householder could be fined up to £5000 for not complying with part P of the building regulations.

As a Gas engineer I would recommend you ring Gas safe to see if your boiler has been registered, they can tell you, if it hasn't it may affect your house insurance, mortgage and may throw a spanner in the works if you try to sell your house Justin