Independent comparisons. We may earn from shop links. More info

Fence post level

Updated: 22 October 2026

A fence post level is the small corner tool that stays on the post while you brace it, so you can see two faces at once. Plumb is only half the job. The post can be upright and still be too tall for the pavement, too close to a neighbour’s foundation, or sat on a cable. This page stays on that fence. How to read the vials, and when a bubble is too big to trust, is [how to use a post level](/hub/measuring-and-marking-tools/post-spirit-level/sub/post-spirit-level-how-to-use). Which of the stored listings has the reviews is the [best post spirit level](/hub/measuring-and-marking-tools/post-spirit-level/sub/post-spirit-level-best) page. Prices sit on the [post spirit level comparison](/hub/measuring-and-marking-tools/post-spirit-level). Peter F. used Planning Portal, legislation.gov.uk, HSE, and the stored amazon.co.uk files on 22 October 2026. This is not legal advice, and it is not a lab test. A qualifying purchase can earn a commission at no extra cost to you.

A fence post level is the small corner tool that stays on the post while you brace it, so you can see two faces at once. Plumb is only half the job.

Our top picks

LSGZJZY LSGZJZY triple bubble

Best overall

LSGZJZY LSGZJZY triple bubble
5.6/10about £5.99
View offer
TIMCO TIMCO 125 mm post level

Alternative

TIMCO TIMCO 125 mm post level
5.4/10about £7.52
View offer
Bubble Levels Bubble Levels 2-pack

Rank 3

Bubble Levels Bubble Levels 2-pack
8.2/10about £9.99
View offer
On this page
  1. 1.Plumb on two faces while the concrete is soft
  2. 2.Timber, concrete, and steel need different fixing
  3. 3.Depth is a rule of thumb
  4. 4.Height, and what is buried

Plumb on two faces while the concrete is soft

UK fencing notes usually say to hold a straight spirit level on two adjacent sides of the post. A post level is that check with the tool strapped on, so both hands can stay on the brace. Adjacent faces matter. Opposite faces can look acceptable while the post leans on the axis you never watched, and you will see the lean in the panel, not in the hole. Seat the corner, pull the band tight, and watch both plumb vials before the mix stiffens. Then brace, and look again. A brace that slips will walk a plumb post off vertical in the time it takes to mix the next hole. A 125 mm body will tell you the post is upright. It will not tell you that a 1.8 m panel between two upright posts is free of bow. For that you still want a straight level along the rail once the posts have taken up, which is the split on the post level vs spirit level page. If the hole is near a neighbour’s foundation, the Party Wall etc. Act 1996 can apply. That is a reason to stop and get advice, not a reason to keep adjusting the bubble.

Timber, concrete, and steel need different fixing

The strap is the fixing for a timber post and for a concrete post. A magnet has nothing to hold on either of them. TIMCO’s Amazon bullets for the 125 mm level, model 468165, name timber, metal, and concrete and call the tool elasticated, which matches that mix, though the Amazon file does not state a vial count. Steel is the case people get wrong. Bare ferrous metal can take a magnet. Coated steel, and a product such as a Durapost, often does not hold the weak magnets that show up in reviews. In 37 stored UK reviews of the folding two-pack, magnets that slide unless the elastic is used are the repeated complaint, including on a steel post. Other reviewers said the magnets held on metal railing posts, so you try the magnet and you do not bet the fence on it. VOANZO’s listing names magnetic strips and does not name a strap. That is a poor match for a timber or concrete run, and it is a gamble on coated steel. Fit the band even when the magnet seems to stick. If the band is missing from the parcel, you do not have the fixing the fence needs. Concrete gravel boards and slotted concrete posts are the same rule: elastic, not hope.
LSGZJZY LSGZJZY triple bubble

Testsieger

LSGZJZY LSGZJZY triple bubble
5.6/10about £5.99
View offer

Depth is a rule of thumb

Depth is a rule of thumb, not a British Standard and not a single legal minimum. DIY Doctor sets out a method used by many UK fencing pages: about one third of the post in the ground, a hole about three times the post width, and, as a worked example, about 60 cm deep for a 1.8 m fence on a 100 mm post. About is doing real work in that sentence. A taller exposed run, a gate post, or soft ground can ask for more, and a fencer is the person who should judge that, not a vial.

Height, and what is buried

Height is law, and it is not the same sentence in every nation. In England, Class A of the General Permitted Development Order generally allows 1 m beside a highway used by vehicles and 2 m elsewhere, and it does not apply in the curtilage of a listed building. The Planning Portal also treats the footway as part of that highway limit, and it flags Article 4 directions that can take the right away. In Wales, a fence over 1 m next to a highway used by vehicles or next to its footpath, or over 2 m elsewhere, needs permission. In Scotland, Class 3E is 2 m, or 1 m if the fence fronts a road or comes forward of the principal elevation. In Northern Ireland the limit is 1 m by a road used by vehicles and 2 m otherwise. A plumb post can still be unlawful. Before you dig, use LSBUD. It covers member assets in Great Britain and it is not a complete map. HSE’s HSG47 is the safe-digging guidance: plan the excavation, and do not encase a service in concrete. If a cable is on the plans, if the height needs permission, or if the post will carry a gate on an exposed site, stop. The bubble cannot settle those questions.

Common questions

Do I check one side of the post or two?
Two adjacent sides. One side can look plumb while the post leans towards the garden or the pavement. Opposite sides are not a substitute for the adjacent pair. Strap the post level so you can see both plumb vials, brace the post, and look again before the concrete stiffens. A straight level does the same two faces one after another if you do not own the corner tool.
Will the magnet hold a steel or concrete post?
Concrete, no. There is nothing ferrous for the magnet to grip, so you use the elastic. Steel, only sometimes. Stored reviews describe magnets that would not hold on a steel post or a Durapost unless the strap was on, and other reviews where they held on metal railing posts. Fit the band either way. A listing that names magnets and no strap is the wrong default for a mixed fence.
How deep should the hole be?
There is no single legal depth in the sources used here. A common UK rule of thumb, set out by DIY Doctor and not by a British Standard, is about one third of the post in the ground, with the hole about three times the post width. Their worked example is about 60 cm for a 1.8 m fence on a 100 mm post. Gate posts, soft ground, and exposed sites can need a different judgement, which is when a fencer should size the hole.
Can I build a 2 m fence next to the pavement?
In England, generally no, if that pavement is a highway used by vehicles. Class A is 1 m beside that highway and 2 m elsewhere, with listed buildings and Article 4 directions as further limits. The Planning Portal includes the footway in that highway case. Wales is similarly 1 m by the highway or its footpath. A post that reads plumb does not create permission. Check the nation you are actually in before you set the height.
Is the height rule the same in Scotland and Northern Ireland?
No. Scotland’s Class 3E is 2 m, reduced to 1 m if the fence fronts a road or comes forward of the house. Northern Ireland is 1 m by a road used by vehicles and 2 m otherwise. England and Wales are closer to each other, and they are still not identical, because Wales names the footpath in the 1 m case. This page is not a planning decision. Your council, or a planning consultant, is the place for a boundary case.
What do I do before I dig?
Ask what is under the grass. LSBUD is the line-search service for Great Britain. It only knows the assets of its members, so a clear reply is not a complete map. HSE’s HSG47 tells you to plan the dig and not to concrete-encase a service if you find one. Paint or mark the line, and stop if the plans show a cable in the hole you were about to fill. A post level does not detect a pipe.
When should a fencer take over?
When a cable is on the plans, when the height needs permission you are not sure you have, when the hole is near a neighbour’s foundation, or when the post will carry a gate on an exposed site. Also when the ground will not hold the rule-of-thumb depth you first marked. The post level still belongs on a straightforward timber run you are allowed to build. It does not replace those stops.

Related pages

Post spirit level buying guide

Post spirit level

Best post spirit level: which listing has reviews

How to use a post level while the concrete is soft

Post level vs spirit level when you already own one

Sources

Public UK sources from the research digest, then the amazon.co.uk listings compared on this page. Shelf prices in this four are the stored listing figures. Draper and Faithfull prices outside the set were captured on 21 October 2026. This is not a laboratory test.

  1. England, GPDO 2015, Class A (gates, fences, walls) (retrieved 21 October 2026)
  2. Consumer Rights Act 2015, section 9 (retrieved 21 October 2026)
  3. BS 958:1968, spirit levels for use in precision engineering (retrieved 21 October 2026)
  4. HSE HSG47, avoiding danger from underground services (retrieved 21 October 2026)
  5. LSBUD, line search before you dig (retrieved 21 October 2026)
  6. TIMCO post level 125 mm, model 468165, trade page (retrieved 21 October 2026)
  7. Draper 75042 on amazon.co.uk, outside this set (retrieved 21 October 2026)
  8. Faithfull FAIPOST on amazon.co.uk, outside this set (retrieved 21 October 2026)