Your mattress silently supports you through countless hours of sleep. But all good things must come to an end.

Whether it's backache in the morning, lumpy materials, or a noticeable lack of edge support, there are plenty of signs your mattress has had it.

Is it time to replace your mattress?

• Age

All mattresses degrade with age, whether regularly slept on or not.

The adhesives that bond foams and fibrous layers break down and turn to powder, the springs that provide support can lose resistance, and the stitching that sews layers together can get snagged and unwind.

A high-quality pocket spring mattress can provide up to eight years of consistent comfort, and an open coil or pure foam mattress can provide up to six years. Ten years isn't unheard of for premium hybrid mattresses.

• Squeaky springs

Your mattress is past its best if it has squeaky springs.

Your mattress's springs shouldn't make a noise even when fully compressed and released – they should operate silently and not be felt through the comfort layers.

Most squeaks occur in cheaper open coil (or Bonnel spring) mattresses, but old pocket springs can also squeak. Squeaks occur when the springs work loose from the surrounding structures and rub against other materials.

• You have persistent aches and pains.

Waking up with aches and pains is a tell-tale sign that your mattress is past it.

For instance, you might always toss and turn to alleviate pain, wake up with sore hips, or have a lower backache first thing in the morning.

These symptoms tell us one thing: your mattress's support core is no longer providing the support you need for optimal comfort.

Remember, we spend about a third of our lives sleeping, so investing in a mattress that helps you sleep comfortably is crucial for your physical and mental health.

• There's visible sagging and degradation.

Sagging is the universal sign that your mattress has reached the end of its life.

Over time, springs fail, and memory foam breaks down, creating dips and valleys that can appear anywhere on the mattress.

You might first notice it as a mild sensation of sinking into the bed, which you remedy by tossing and turning or sleeping right at the edge.

The worst part about mattress sagging is that it happens gradually, often unnoticed, until it's so severe that you roll into the middle of the bed.

Depressions are usually more noticeable than sagging because they are confined to smaller areas (usually where your shoulders and hips go).

• It stinks, and you can't remedy it.

Over the years, mattresses accumulate dead skin cells, dust, dust mites (and their droppings), mould, bacteria, pollen, and other airborne nasties.

Add bodily fluids and a few random drink spills over the years, and it's no wonder old mattresses don't smell very good.

A wet vacuum cleaner and good airing can solve most mattress smells, but sometimes, the grime is too deep and persistent to clean.

The best option is to replace your mattress, although if you can't afford to, you could cover it with a waterproof mattress topper.

• Uneven comfort levels

One side of your mattress might be more supportive than the other or have a plusher comfort layer because one side is less compressed.

For mattresses under five years old, these symptoms usually result from not rotating or flipping the mattress to even out the wear — rotate the mattress, which should even out over three to six months.

However, if your mattress is over five years old and has a distinct difference in comfort levels, the support system is probably caput.

Try sleeping on both sides of the bed and see what you think. If your mattress feels like it's playing favourites, it might be time to show it the door.