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Extension lead for a lawnmower: unwind on dry grass

Updated: 23 October 2026

The grass is long, the mower’s own cable stops halfway across the lawn, and the reel in the shed says outdoor on the box. An extension lead for a lawnmower is a temporary feed for one corded mower, or for a strimmer used the same way. It is not a second lead joined on, and it is not a reason to mow while the grass is wet. The table is the [outdoor extension lead comparison](/hub/sockets-and-extension-leads/outdoor-extension-lead). The Products Compared editorial team used Electrical Safety First’s lawnmower and garden pages, plus the amazon.co.uk listings, on 21 October 2026. It is not a lab test of any mower. A qualifying purchase can earn a commission at no extra cost to you.

The grass is long, the mower’s own cable stops halfway across the lawn, and the reel in the shed says outdoor on the box.

Our top picks

SLx SLx 90025PI 20 m

Best overall

SLx SLx 90025PI 20 m
9.0/10about £34.99
View offer
SLx SLx 90073PI/14 30 m

Alternative

SLx SLx 90073PI/14 30 m
7.6/10about £44.99
View offer
SLx SLx RM 10 m reel

Best value

SLx SLx RM 10 m reel
8.2/10about £19.99
View offer
On this page
  1. 1.Dry grass and an RCD first
  2. 2.Unwind, and keep the cable out of the blades
  3. 3.Which leads in this set mention a mower
  4. 4.One tool on a 13 A lead

Dry grass and an RCD first

Electrical Safety First says not to mow in wet weather, and not to use the lead in a wet area. Dew is already a reason to wait. An outdoor word on a reel does not dry the grass. If you cut a cable, the device they point to is a 30 mA RCD on the supply, not a slogan on the drum. None of these seven listings contains that RCD. A thermal cut-out opens when the reel overheats. It does not trip because a blade has nicked the live conductor. If you cannot tell whether the socket has 30 mA protection, stop and ask a registered electrician. The reel will not add it on the lawn. Wickes’ buying guidance tells you to look at the mower’s own cable before you buy an extension. A high-visibility lead does not repair a damaged flex. The wider order of checks is the outdoor extension lead buying guide.

Unwind, and keep the cable out of the blades

Electrical Safety First’s lawnmower page says that if you must use an extension lead it should be suitable for outdoor use, have a thermal cut-out, and be fully unwound. Their grass-trimmer page adds the position: keep the cable over your shoulder and out of the cutting path. Lay the spare behind you, in the area you have already cut, not across the strip you are about to mow. The only listing here that prints a wound current is the 15 m Status reel: 5 A wound and 13 A unwound. Philex’s examples put a typical electric lawnmower at about 1,200–1,800 W, roughly 5–7.5 A, so that 15 m reel still comes off the drum. The other reels do not print a wound figure on amazon.co.uk. The trip steps, if the cut-out opens, are how to use a cable reel.
SLx SLx 90025PI 20 m

Testsieger

SLx SLx 90025PI 20 m
9.0/10about £34.99
View offer

Which leads in this set mention a mower

Three listings actually say lawnmower, and they are not interchangeable. The 10 m four-socket SLx at £19.99 names a lawnmower in the bullets, with 4.6 from 1,660 reviews on that ASIN, a thermal cut-out, and no IP code. Ten metres is enough when the socket is close to the lawn and you will unwind all of it. It is short if the socket is on the far side of the house. Reviewers also say the winder tangles. The 20 m SLx 90025PI at £34.99 also names a lawnmower, and it is the only listing that prints IP54, on two covered sockets. Splash is not a wet lawn, and you still unwind it. The 30 m SLx names a lawnmower too, prints no IP code, and its instruction sheet says not to use that family in damp conditions.

One tool on a 13 A lead

The Philex sheet puts pressure washers at about 1,800–3,000 W beside those mower examples. Two of those loads on one lead can pass 13 A. Four sockets do not add a second fuse. If you want to wash the patio after you mow, unplug the mower first. The straight Etykir lead is not the mower lead in the wet. It is 10 m with three sockets, and several UK reviews say the instructions say indoor use only, or not for damp or wet conditions. No IP code is printed. Do not send a corded mower out on that bar because the title says outdoor.

Common questions

Can I mow on wet grass with an outdoor lead?
No. Electrical Safety First says not to mow in the wet and not to use the lead in a wet area. Dew counts. IP54 on the 20 m SLx means splash at covered sockets, not a wet lawn. The 30 m SLx instruction sheet says not to use that model family in damp or wet conditions. Wait until the grass is dry, then unwind the reel.
Do I unwind the reel for a mower?
Yes. The lawnmower page from Electrical Safety First asks for a full unwind and a thermal cut-out. A mower in the Philex examples is about 1,200–1,800 W, roughly 5–7.5 A, which can sit above the 5 A wound mark on the 15 m Status and above the 960 W wound figure Philex prints for the named SLx models. Pull the cable off before you start, including the metres you think you will not need.
Which listing names a lawnmower and prints IP54?
The SLx 90025PI, 20 m, two covered sockets, £34.99 in the snapshot, 4.6 from 4,160 reviews on that file. The bullets say splashproof. The title says waterproof. You still mow on dry grass, with the covers shut and the cable fully out. The 10 m and 30 m SLx reels also name a lawnmower, and they do not print an IP code.
Is 10 m enough?
It is enough when the socket is within 10 m of the grass you need to cut and you will unwind the whole reel. That is the case reviewers describe for the £19.99 four-socket SLx. It is not enough if the cable has to run through the house and down the garden. Do not add a second lead to make up the difference. Buy a length you can empty, or use a closer socket.
Will four sockets run a mower and a pressure washer together?
Not safely, on the Philex example figures. A mower at 1,200–1,800 W plus a pressure washer at 1,800–3,000 W can pass a 13 A fuse. The four sockets on the 10 m SLx, the 25 m Status and the 30 m SLx share one plug. Finish mowing, unplug, then wash. A spare socket is for a light load, not for a second heavy tool.

Related pages

Cable reel or straight lead

Outdoor extension lead

Best outdoor extension lead: splash, reach or 10 m

Outdoor extension lead buying guide for a UK garden

How to use an outdoor cable reel: unwind it first

Sources

Sources taken from the research digest. Listings were scored on 21 October 2026. This page did not run a lab test.

  1. Electrical Safety First — leads and reels (retrieved 21.10.2026)
  2. Electrical Safety First — garden (retrieved 21.10.2026)
  3. Electrical Safety First — lawnmowers (retrieved 21.10.2026)
  4. Electrical Safety First — overloading (retrieved 21.10.2026)
  5. IET Wiring Matters — regulation 411.3.3 (retrieved 21.10.2026)
  6. NICEIC — garden electrics (retrieved 21.10.2026)
  7. SI 1994/1768 — plugs and sockets (retrieved 21.10.2026)
  8. Clarion UK — IP codes (retrieved 21.10.2026)