The cost of mould removal in a UK rental property typically runs from around £150 to £450 for a straightforward single-room treatment, rising to £600-£1,200 for larger affected areas, and considerably more where the underlying cause is structural. But the price of the treatment is rarely the most important figure for a landlord or property manager. The real cost question is what happens when mould is not treated properly - or not treated at all.
Mould that is painted over, cleaned once and left to return, or dismissed without investigation does not stay cheap. It spreads, the moisture damage underneath accumulates, and the exposure to tenant health risk and legal liability grows with every week of delay. This guide sets out what professional mould removal actually costs in the UK, what drives the price, and how to think about that cost alongside the consequences of inaction.
What affects the cost of mould removal
No two mould jobs are identical. The price depends on several factors that are specific to the property, the extent of the growth, and what is causing it.
- Size of the affected area - a small patch on a bathroom ceiling is a different job from mould covering two walls of a bedroom and spreading into the corner of an adjoining room.
- Surface type - painted plaster is the most straightforward to treat. Bare or damaged plaster, plasterboard, and timber each hold moisture and mould root structures differently and may need more intensive treatment or partial replastering.
- Whether the cause has been identified and fixed - treating mould without addressing the moisture source means the job has to be done twice. A professional contractor will inspect for the cause as part of the visit, and any underlying issue such as a broken extractor fan, a failed window seal, or penetrating damp adds to the scope and cost.
- Depth of penetration - surface mould on paint responds well to a professional fungicidal wash. Mould that has penetrated plaster or is growing through plasterboard requires more intensive treatment.
- Redecoration - mould treatment leaves surfaces that need repainting. Some quotes include preparation and redecoration; others price this separately. Check what is covered before accepting a quote.
- Location - labour costs in London and the South East are generally higher than elsewhere in England.
Typical cost ranges for mould removal in the UK
The figures below reflect the general market for professional mould treatment in England as of 2026. They are indicative - the right price for a specific job depends on a proper inspection, not a figure from a guide.
| Scale of problem | Typical cost range |
|---|---|
| Single room, surface mould on painted plaster | £150 - £450 |
| Medium contamination, 2-3 rooms | £600 - £1,200 |
| Extensive mould or structural moisture involved | £1,500 - £3,000+ |
| Full property remediation including damp works | £3,000 - £5,000+ |
What a professional mould treatment should include
A professional mould treatment is more than a chemical application. The things that separate a treatment that holds from one that does not are the inspection beforehand and the follow-through on the cause. A sound job includes:
- An inspection with damp meter readings to confirm the moisture source before any treatment begins.
- A professional-grade fungicidal wash applied with the correct dwell time - not a diluted retail product.
- Surface preparation before any redecoration: the mould must be killed and the surface completely dry before paint is applied.
- A written record of findings and works - this is what landlords need for compliance and to protect themselves if a claim follows.
- Advice or direct remediation on the underlying cause: ventilation improvement, seal replacement, or referral to a damp specialist.
The cost of not treating mould
For landlords, the cost of professional mould removal is relatively straightforward to budget for. The cost of leaving mould untreated is much harder to cap - and it almost always ends up being higher.
The mould spreads and the damage accumulates
Mould is a living organism. Left in place, it spreads to adjacent surfaces, penetrates deeper into plaster and behind finishes, and the moisture driving it continues to damage the building fabric underneath. A job costing a few hundred pounds to treat at first report can become a full replastering and damp-proofing project if ignored for a year. The savings from delay are rarely real.
Legal liability: disrepair claims and council enforcement
Mould in a rented property is not a cosmetic issue under UK law. A landlord who receives a mould report and does not investigate and fix the cause within a reasonable time is in breach of their duties under Section 11 of the Landlord and Tenant Act 1985 and the Homes (Fitness for Human Habitation) Act 2018. The Renters' Rights Act 2025, in force since May 2026, has strengthened tenants' enforcement tools and removed the risk of retaliatory eviction for tenants who report disrepair.
A housing disrepair claim brought under the Homes Act can result in a court order requiring works to be done plus compensation for the period the tenant lived in an unfit property. Legal costs for a claim that proceeds to court routinely exceed the cost of the original repair by a significant margin. Local council enforcement under the Housing Health and Safety Rating System can also result in an improvement notice with a fixed compliance deadline and penalties for failure to act.
For more on your legal duties when mould is reported, see our guide to mould in a rental property: a landlord's legal duties. This post is general guidance, not legal advice.
Void periods and re-letting costs
Untreated mould discovered between tenancies - or mould that causes a tenant to leave - creates a void period on top of the remediation cost. The cost of an empty property (lost rent, council tax where the landlord pays it, utilities) quickly eclipses the cost of a professional mould treatment. A two-week void on a London rental property can cost more than a full single-room mould remediation. A property with visible mould also tends to sit empty for longer and re-let at a lower rent.
DIY mould removal: when it works and when it does not
DIY mould removal with household products is a reasonable first step for a small surface patch on a painted bathroom ceiling or a mouldy silicone bead. It becomes the wrong choice in several situations:
- Where the same patch has returned two or more times after cleaning - there is an unresolved moisture source that needs professional diagnosis. See why does mould keep coming back for the most common causes.
- Where the affected area covers more than roughly a metre square.
- Where the mould is on bare plaster, plasterboard or timber, where retail products do not penetrate effectively.
- Where there is any suspicion of a structural cause - penetrating damp, a hidden leak, or a failed damp-proof course.
- Where there is a formal tenant complaint or the property is subject to a council inspection. Professional treatment with a written report is the right approach here.
Our guide to how to get rid of black mould on walls for good covers the correct treatment method for surface mould, including the products that work and the ventilation improvements that stop it coming back.
How to get a fair quote for mould removal
Any quote given without an inspection or at least a photo of the affected area should be treated with caution. Price alone is a poor basis for choosing a mould contractor. Questions worth asking before instructing anyone:
- Do they inspect the cause as well as treating the visible mould, or only treat the surface?
- Do they use professional-grade fungicidal products, or retail mould sprays applied more frequently?
- Do they provide a written report of findings and works? This matters for your landlord records.
- Is redecoration included, or priced separately?
- Is there a guarantee? A 12-month guarantee on the treated area is standard for professional work - if the mould returns within that period, the contractor comes back.
- Are they insured and accredited? Constructionline Gold or a similar scheme gives assurance that the contractor meets a recognised standard.
How Simpled Services approaches mould removal costs
We deal with mould removal across London and the South of England for letting agents, housing associations, councils and private landlords. A photo on WhatsApp is usually enough for us to give you a clear indication of the scope and cost before we visit - it is the fastest route to an informed quote.
Our mould treatment covers inspection, professional-grade fungicidal treatment of the affected area, a written report of what we found and what we did, and a 12-month guarantee on the treated areas. Where the underlying cause needs addressing separately - a ventilation improvement, a plumbing repair, or damp-proofing works - we will tell you exactly what is involved and at what cost. We have completed over 8,500 jobs and hold Constructionline Gold accreditation.
If you need a hand, Simpled Services can help. Call us on 020 4571 7367, message us on WhatsApp at the same number (020 4571 7367), or email hello@simpledservices.co.uk and we will take it from there.