This depends on your body type, general sleeping position, and type of pain you're experiencing. We can't cover all situations, but can provide some general guidance:
Those experiencing discomfort or pain from pressure points (usually when some part of your body gets pressed or pinched when they're supporting too much weight) will usually benefit from moving to a softer mattress. Side sleepers on very firm mattresses can often have their arms and shoulders pinched between their body and the mattress. Any of our taller 25cm mattresses should help. While they're softer, these mattresses are still considered 'medium' in firmness, and have been tested for great spinal alignment, for those concerned about overly saggy soft mattresses.
Those experiencing back pain from a lack of spinal alignment (usually because a mattress is too soft and starts to sag in the hip area), will often benefit from using something more supportive - best provided by one of our hybrid spring mattresses. This issue happens more frequently to people who are heavier, are older (and may have weaker back muscles), or have simply slept in very old deformed mattresses for too long. They will benefit well from any of our Hybrid spring mattresses to avoid any pressure point problems mentioned in the prior paragraph.
For more nuanced advice, get in touch with our Sleep Experts who will be happy to help you find the right sleep system for you.