Washing Machine Not Draining? Machine or Plumbing Fault

When a washing machine won't drain, the water is stuck either inside the machine or in the waste pipe it drains into. Inside the machine, it's usually a blocked pump filter, a kinked drain hose or a failed drain pump. In the plumbing, it's a blocked sink trap, spigot or standpipe, or on a new installation, a spigot whose blanking cap was never removed. The quickest way to tell: if the kitchen sink also drains slowly or gurgles when the machine empties, the blockage is in the shared waste and a plumber can clear it. If the sink is fine and the machine hums without pumping out, the fault is in the machine.

Machine or plumbing?

What you notice	Most likely
Kitchen sink slow, gurgling or backing up when the machine drains	Blocked sink trap, spigot or waste pipe
Water comes up out of the standpipe onto the floor	Blocked standpipe trap or waste pipe
Machine hums but no water moves, sink drains normally	Blocked filter or failed drain pump
Drains slowly and leaves water, with a smell of damp lint	Filter or hose partly blocked
Error code on the display, sink fine	Machine fault. Check the manual for that code.
Brand new machine or new sink trap, never drained properly	Kinked hose, or blanking cap left in the spigot

If you have a dishwasher on the same sink trap, it's a useful clue. If the dishwasher is struggling too, the blockage is almost certainly in the shared trap or waste.

Get the water out safely

1. Switch off and unplug the machine. Don't open the filter with it plugged in.
2. If it's just finished a hot wash, give it time to cool.
3. Put towels down and a shallow tray or baking dish under the filter hatch, which is usually at the bottom front behind a small flap.
4. Many machines have a small emergency drain tube next to the filter. Pull it out, remove its cap and let the water run into the tray. Close it and empty the tray as often as you need. There can be a lot of water.
5. Once the flow stops, unscrew the filter slowly anticlockwise.

Your machine's manual shows exactly where the filter is and how it comes out. Some are behind the kick plate.

Checks on the machine

• The pump filter. This is the most common cause. Clean out lint, hair, coins, hair grips, buttons and bra wires, rinse the filter under the tap, and check the space behind it. If you can reach the pump impeller with a finger, it should turn. Refit the filter firmly so it doesn't leak.
• The drain hose. Pull the machine out and look for kinks or a hose squashed against the wall. A hose that's been pushed too far down a standpipe can also siphon or block.
• The hose itself. Disconnect it at the waste end, hold it over a bucket and check it's clear. Lint builds up at bends.

Then do the bucket test. With the hose end in a bucket held low, plug the machine in and run a drain or spin programme. If water comes out strongly, the machine works and the problem is in the waste. If little or nothing comes out and you hear humming, the drain pump is probably failing. That's a job for an appliance engineer or the manufacturer, not a plumber.

Checks on the waste

Washing machines drain into either a spigot on the kitchen sink trap or a standpipe, which is an upright pipe with its own trap.

Sink trap and spigot. Put a bowl under the sink trap, undo the plastic nuts by hand and take the trap off. Lint and grease collect in the bend and inside the spigot. Clean both, check the rubber washers are in place, and refit hand tight. Run the tap and check for drips. If the sink is still slow with the trap clean, the blockage is further down the waste pipe. Our guide to a blocked kitchen sink goes through clearing it.

Standpipe. If water comes up out of the standpipe, the trap at its base or the pipe beyond is blocked. Some standpipe traps unscrew for cleaning. If yours doesn't, or it's boxed in, a plumber can clear it.

Don't pour boiling water or strong drain chemicals into a waste with a washing machine hose on it. Chemicals can sit in the trap and splash back when you take it apart, and very hot water can damage plastic waste fittings.

Just installed and won't drain

If the machine is new, or the sink trap or standpipe has just been fitted, check these before anything else:

• The spigot blanking cap. New sink traps with a washing machine spigot often come sealed so they don't leak when nothing is connected. The seal has to be removed before the hose goes on. If it's still in place, the machine can't drain at all.
• Transit bolts and packaging. Your manual will tell you to remove these before the first wash.
• Hose height. Each machine's manual gives a height range for the drain hose. Too low and water can siphon out while it fills. Too high and the pump can struggle. The hose should loop up above the drum before dropping into the waste.
• No trap. A hose pushed straight into an open pipe with no trap lets drain smells into the room. Waste connections need a trap to keep a water seal between the room and the drain, which is what Approved Document H sets out. If you're noticing a smell as well, see our guide to a sewer smell from a washing machine.

When to call a plumber

Call a plumber when the machine works in the bucket test but the waste won't take the water, when the sink backs up or water overflows from the standpipe, when the waste has no trap or sits at the wrong height, or when the trap is cracked or keeps leaking after you've cleaned it. If you're in a flat, don't leave a backing-up waste overnight. Water that spills behind the units can go straight through to the flat below.

If the machine itself is at fault, contact the manufacturer or an appliance repair engineer. If water is appearing under the machine rather than failing to drain, see our guide to a washing machine leaking. And if you're moving or replacing the machine, our washing machine plumber guide explains when new plumbing is needed.

We charge £95 an hour for labour, plus a £60 call-out that's waived when the job runs over 2 hours. Parts are extra and we confirm the price before any work starts. Our blocked sink and kitchen plumbing services cover traps, spigots, standpipes and waste pipes across London, and the pricing page explains how jobs are charged.

Frequently Asked Questions