costs
Cost to unblock an outside drain in the UK (2026)
Standard outside drain unblocks in the UK are £80–£180 + VAT. Here's what affects the price and what to ask before you book.
Most UK drainage firms charge between £80 and £180 + VAT for a standard outside drain unblock. Here's what affects the price and how to make sure you're not overcharged.
What's a 'standard' unblock?
- One blockage
- Accessible from one chamber (manhole)
- Clearable with rods, a drain machine or a small jetter
- Cleared inside about an hour
Most domestic outside-drain blockages fall into this category.
What pushes the price up?
- Multiple chambers to rod through — typically adds £40–£100.
- Awkward access (paving over the chamber, locked side-gate, raised manhole covers under decking).
- Heavy root mass or large fat plugs — usually need jetting rather than rods.
- Out-of-hours callout: most reputable firms don't charge extra for nights or weekends — if a quote suddenly doubles after 6pm, push back.
What to ask before you book
- Is there a callout fee? A reputable firm comes out free and only charges if you accept their written quote.
- Is the price fixed? Avoid hourly rates without a cap — drainage is unpredictable.
- Is VAT included? Domestic prices usually quoted ex-VAT. Add 20%.
- What's covered if it doesn't clear? A good firm doesn't charge for a job they couldn't fix.
Red flags
- £29 callout adverts that turn into £300+ on site
- Cash-only with no invoice
- Pressure to authorise a 'CCTV survey' or a repair before you've seen the camera footage
If in doubt, get a second written quote. Drainage is a competitive market and any honest engineer will be happy for you to.