Life rafts should be serviced before the season starts, warn the RYA. Many contain a number of items of survival equipment such as torches, flares, first aid kits, anti-seasickness pills, water and food that all have a shelf life and must be changed when they expire.

It is also vital that the inflation system has not leaked and still has enough gas to inflate the life raft and achieve working pressure.
It is worth remembering that valise-packed life rafts are prone to internal damage if they are moved about regularly or not stored properly and for that reason the MCA stipulates that they are serviced annually where carriage is mandatory.

Some time ago, the RNLI set off a life raft in their pool when testing hydrostatic releases, what came out were two tractor tyre inner tubes and a pile of house bricks to make up the weight! You do not need to find that out when abandoning ship, says RYA cruising manager Stuart Carruthers.

In the UK, the MCA requires inflatable life rafts, marine evacuation systems, inflatable lifejackets and hydrostatic release units carried on United Kingdom merchant ships, fishing vessels and small commercial vessels (including charter and RYA recognised training centre craft) to be regularly serviced at an Approved Service Station.

An Approved Service Station is one that has been formally accredited by the manufacturer of the equipment and has been approved by the MCA on behalf of the Secretary of State.
 
There is no such requirement for servicing of privately owned leisure inflatable life rafts; you are free to get it serviced when you like and by whom you like.

Although many service stations offer servicing for a wide range of life raft models, they may not be approved by the manufacturer to do the work. Be aware that any service work done by a non-approved service station could invalidate a life raft warranty.

The MCA provides further advice and Standards for the Conditions for the Approval of Service Stations for Small Craft Inflatable Liferafts.