Blocked drain outside your house: cost and who pays

A blocked drain outside your house costs you nothing if it is the road gully at the kerb, which is the council's, or the public sewer, which is Scottish Water's. If it is your own drain, a 2026 UK price guide puts a typical clearance at £80 to £250 including VAT, and says London and the South East run 15 to 30% dearer than Scotland. So the first question is not the price. It is where the blockage is. This guide shows the five places it can be, who pays for each, and what to send for a fixed quote. If it turns out to be yours, our drain unblocking service covers Alloa and Central Scotland.

Five places a blocked drain outside can be, and who pays for each

"Outside the house" covers very different pipes. Scottish Water says your private drain runs from your home to your property boundary, where it meets the public sewer, and that the homeowner is responsible for that pipe. It also says local authorities are responsible for draining local roads, and that private pipework inside the boundary is the homeowner's. Put those three statements side by side and most outside blockages sort themselves into one of five places.

The table uses "usually" and "generally" on purpose. Older homes, shared closes and estates can have drains that do not follow the simple pattern, and the exact line is set out in our guide to who is responsible for blocked drains in Scotland. What the table does is stop you paying for a road gully or a public sewer by mistake.

What a private blockage outside costs

When the blockage is on your side of the boundary, the bill is yours. Fantastic Services' 2026 drain unblocking guide gives these figures for the UK outside London and the South East, and says its figures include VAT. These are market ranges from a national firm, not CB Drainage prices.

The same guide puts an average straightforward job at £90 to £150, and says prices in London and the South East run roughly 15 to 30% higher than in the North of England, Wales and Scotland. It also says same-day, evening, weekend and bank holiday call-outs carry a premium, without giving a figure. For a second set of figures, our drain unblocking cost guide for Stirling and Falkirk uses Checkatrade's 2026 averages and three worked examples.

VAT: read the quote twice

The standard rate of VAT is 20%, and GOV.UK says a business must register once its taxable turnover goes over £90,000 in a rolling 12 months. Plenty of local drainage engineers trade below that and do not charge VAT at all. That makes two quotes with the same headline figure very different:

• A quote of £150 plus VAT from a VAT-registered firm is £150 × 1.2 = £180 to pay.
• A quote of £150 from a trader who is not VAT registered is £150 to pay.
• Going the other way, a jetting job at the top of the guide's range, £125 including VAT, is £125 ÷ 1.2 = about £104 before VAT.

So ask one plain question before you agree anything: "Is that the total I will pay, including VAT?"

The road gully: report it, do not pay for it

The grating in the road channel outside your house drains the road, not your home. Scottish Water lists road drainage as a local authority job, and the three councils around Alloa each have their own route.

• Stirling Council. Its page on blocked or broken drains, updated 30 July 2026, says falling leaves can be a major cause of blocked drains in autumn, and that clearing leaves from a drain near your home, when it is safe, can help stop large puddles forming. It also says drains can be slow in heavy rain or ice because of capacity rather than a blockage. If a drain does not clear, report it on the council's form. If a blocked drain is sending water into your home, the roads team may be able to attend on 01786 404040.
• Falkirk Council. Blocked road drains are reported online as a road defect, alongside potholes and trip hazards. On 8 October 2026 the council said it cleaned 33,750 gullies in 2025/26, 93% of its network, and that a third year of full-network cleaning is under way.
• Clackmannanshire Council. Its flooding page says most minor flooding in late autumn and early winter happens because drain openings are blocked by fallen leaves, and asks residents to clear leaves from gully grates where safe. Urgent problems go to 01259 450000, and drainage concerns to roads@clacks.gov.uk.

Two of the three councils say the same thing about leaves, and it matters for your own gullies too. A grate covered in wet leaves often looks like a blocked drain when the pipe itself is fine. Lift the leaves off with a gloved hand before you assume the worst. Our guide to clearing a blocked gully yourself sets out the safe steps and the point to stop. If you are in Stirling or Falkirk and the water is on your side of the kerb, it is not the council's job.

Why an outside job can cost more than the clearance

The method is often the cheap part. The price moves with what stands between the engineer and the pipe:

• Covers set into paving. A recessed cover filled with block paving has to be lifted carefully and reset, and a cover that has been paved over has to be found first.
• Distance from the nearest chamber. A blockage halfway along a long run is harder to reach than one beside a gully, and that is where jetting tends to come in.
• Repeat blockages. If the same drain blocks again within months, a clearance only treats the symptom. The guide's £90 to £200 for a camera survey is the step that shows whether scale, roots or a broken joint is the cause.
• Digging. Excavation starts at around £600 on the same guide, and a drive or patio has to be put back afterwards.

None of that is a reason to put it off. Knowing which of these applies before anyone arrives is what lets you compare quotes on the same job.

What to send for a fixed quote

A firmer price comes from a few details rather than a vague description. Before you call anyone, gather these.

1. Where the water appears

   The road gully, a gully at the house, a chamber in the drive or garden, or inside the house.

2. A photo of the open chamber

   If you can lift a cover safely, photograph the water level inside. A full chamber and an empty one tell different stories.

3. Whether neighbours are affected

   If their chambers or gullies are backing up as well, the shared run or the public sewer is more likely, and Scottish Water should be your first call.

4. The access

   Covers in block paving, under a shed or behind a locked gate all change the job.

5. How often it has happened

   A first blockage and a third one in a year need different answers.

6. The VAT question

   Ask for the total, including VAT, and what is included if a camera survey is needed.

Send those to us through the quote form or call Brian, and he will tell you what he thinks the job is before you agree anything.

If it turns out to be the public sewer

Scottish Water's customer line is 0800 0778 778, open 24 hours. If a blockage could be in a shared run or past your boundary, ring before you pay a firm. Our guide on whether Scottish Water unblocks drains for free covers what it does and does not pay for.

A 2014 decision by the Scottish Public Services Ombudsman shows why it is worth a written record. A couple were told by Scottish Water that a blockage was theirs to resolve. Their contractors found it lay under the public footpath, which Scottish Water later confirmed. Scottish Water first refused to refund their costs, then offered 50%. The Ombudsman found Scottish Water was entirely responsible for the blockage under the footpath and upheld the complaint about costs. If a firm clears a blockage outside your house, ask them to write down where they found it.

Why some outside drain advice does not fit Scotland

A common line in UK price guides is that since October 2011, shared drains and pipes beyond your boundary belong to the water company, so clearing them is free. That transfer happened in England and Wales. Scotland never had it: its definitions of drains and sewers come from the Sewerage (Scotland) Act 1968, so a guide written for England can mislead you about a shared drain here. Our Scottish responsibility guide goes through the 1968 Act definitions.

The short version for an outside blockage: find where it is, check whose it is, and only then compare prices. Our drain unblocking page has the details if the drain is yours, and the advice hub has the rest of our guides.

Keep reading: blocked drain in a rented home: landlord or tenant to pay?

Keep reading: Blocked drain in the back garden: causes and fixes.

Keep reading: Toilet still blocked after plunging? What to do next.