Most mattresses are said to last 7-10 years. Or somewhere between. The number works out if you buy the mattress yourself. But how would you know the age of a mattress that came with the rented flat? Nobody knows its age, how many tenants it carried, or how many relocations it survived. That’s how the decision around replacing a mattress gets difficult. When should you replace a mattress if you did not buy it in the first place? How do you know it’s the right time?
When you are getting the mattress from the landlord, the replacement cost falls on the landlord. Households choosing to rent a mattress through furniture rental platforms shift part of the problem, as repairs and replacements remain the mattress owner’s responsibility.
When Should You Change the Mattress?
The recommended period is 7-10 years from the purchase date. The range works only when the mattress survives one household. In shared or rented apartments, the mattress lifespan may be less than 7 years.
The guideline is a rough estimate of how long foam and coils resist a household’s nightly load before pushing back. Multiple tenants, relocation, and a gradually sagging cot can accelerate the mattress’s deterioration.
Should You Change a Mattress if it Looks Fine?
The part that wears out is the support layer – it is not the surface. When there is no support, the spine does not stay aligned, and the body compensates all night instead of resting. A mattress may look fine, but it may stop functioning.
What to Test before Replacing the Mattress
In 5 minutes, you can find out whether you should replace the mattress.
- Look along the surface. Strip the bed completely. Crouch at the foot and sight down the length. A dip that is visible with nothing on the mattress is a real dip.
- Lay the straight edge across it. Rest it over the middle, running side to side. A gap you can slide a fist under is significant. A gap that takes two fingers is early.
- Press along the length. Push down with a flat palm every foot or so. You are looking for one zone that gives noticeably more than the rest, usually where the hips land.
- Do the roll test. Lie in your usual spot, then in the middle. If the mattress rolls you toward the centre, or toward the person next to you, the core has lost its shape.
- Sit on the edge and listen. The edge should hold you at roughly seated height. A collapse, a grind or a metallic creak under ordinary movement is a structural signal, not a noise problem.
If two things fail at the same time, you get your answer. If there is one thing to consider when something is failing, it’s that not every fault means replacement.
| What you found | Usual cause | Repairable or replacement needed |
| Even, shallow softening across the whole surface | Normal comfort-layer fatigue | Repairable — a firm topper buys real time |
| Dip in one sleeping zone only, mattress otherwise firm | Support loss under load | Replacement needed— a topper hides it, does not fix it |
| Dip that matches the frame underneath | The base, not the mattress | Repairable — fix the base first |
| Edge collapses when you sit on it | Perimeter or border failure | Replacement needed |
| Metallic poke, grind or creak | Broken spring | Replacement needed |
Broken Spring in a Mattress: Should You Repair or Replace?
A broken spring does not settle down with time – it is a structural failure. There are three things you might notice:
- A hard point that pokes through when you shift weight
2. A grinding or twanging noise on movement
3. A hip that sinks further on one side than the other
To confirm whether the spring is broken, you can strip the bed and press directly over the spot the noise comes from. A failed coil feels like a hard object rather than a soft dip, and you will hear the same sound at the same place every time.
It matters more than a sag because a coil rarely fails alone. Repair is not a realistic choice – working on the spring means opening the cover. The covers on modern mattresses are often not designed to be reopened.
Morning Stiffness Indicates a Mattress Replacement
If you wake up every day with a stiff back that eases later, you should take it seriously. Most of the time, a new mattress does not feel comfortable – your body has been used to the old one.
To confirm whether the mattress replacement is needed, check if you feel similar stiffness when waking up on a different bed. If you feel better rested on a hotel bed or another bed, you should consider replacing the mattress. When the pain does not go away, it may be a different matter, and you should consult a doctor.
How to Check the Used Mattress?
If you are considering buying a second-hand mattress, you should check three things:
- Turn it over. Stains, tape, stitching repairs and a compressed, discoloured band along one edge tell you how it has lived.
- Ask how it was stored. Months upright against a wall, a fold to fit a vehicle, or a spell on the floor all cause damage that does not show on the surface.
- Ask what it sat on. A mattress that spent 3 years on a wide-slatted cot arrives pre-shaped, and it keeps that shape on your bed.
Sometimes you can get a free mattress from your landlord, and it is a fair trade when you know you will leave the place in a few months. Sometimes a firm topper also helps an evenly softened mattress. However, the topper changes what you feel.
Should You Rent or Buy a New Mattress?
The answer depends on how long you are willing to stay in one place. Buying a mattress is amortised over years of use, so the numbers depend on getting those years. If you buy a mattress after moving to a new place, ask yourself whether you will move again. Every move ages the mattress a bit.
Replacing a mattress with a new one is suited to permanent residents. In this case, the bed base remains in one place. Renting a mattress matches the opposite situation. In shared apartments, in a city where you are unsure of how long you will stay, or for anyone on a short-term lease – a mattress rental from Rentomojo runs on a 3-month minimum tenure and free repairs.
Final Thoughts
When to replace a mattress depends on how you feel, not on when you bought it. You can fix the base before deciding on when to replace the mattress. Use a topper where the softening is even, and skip it where the support has actually failed. Treat a broken spring as a replacement rather than a repair. And decide between buying and renting based on how settled the next two years look, because that, more than anything on the label, decides what an early mattress replacement will cost you.