Are these legal minimums or recommended sizes?

The first figure is the legal minimum under Schedule 8 — an absolute floor, not a target. The second, RSPCA Assured, is a genuine higher-welfare certification scheme. DEFRA's Code of Practice for the Welfare of Pigs says more space may be needed but doesn't publish a number. The RSPCA's separate advice for people keeping pigs as pets does give one — a minimum of 36 square metres per pig, ideally more — but it is pet-keeper advice rather than a farm standard and its wording doesn't say whether that means covered or total area, so the calculator shows only the two figures with a published standard behind them and the guide on how much space a pig needs discusses the RSPCA advice.

Does a pig's weight affect how much space it needs?

Yes. Both the legal minimum and the RSPCA standard scale with average group weight — from 0.15m² for piglets under 10kg up to 1m² for pigs over 110kg under Schedule 8. Heavier pigs need more space per head, not just more total space for more pigs.

Can two pigs share a pen?

Yes — pigs are social animals and are almost always kept in groups rather than singly. The figures above are already group allowances (a per-head share of a shared pen), which is how Schedule 8 and RSPCA Assured expect pigs to be housed.

Does the calculator include outdoor space separately from indoor shelter?

Yes, if you select outdoor housing. Paddock land (12m² per pig rotated to fresh ground, or 40m² per pig on static ground) is a separate figure from the shelter or ark size — free-range pigs need both, not one or the other.

Does this apply if I only keep a couple of pigs?

Yes. The per-pig space requirements in Schedule 8 apply regardless of how many pigs you keep — there's no small-holding exemption from the space standards themselves.

What if my pigs are different weights?

Use the average weight of the group. If there's a wide spread, it's safer to size the pen for your heaviest pigs.

Is there a version of this for the US?

Yes — see the US pig pen size calculator, based on the National Pork Board's standard.

Pig Calculator

How much space do your pigs actually need?

Enter your group size and weight to get a straight answer — drawn from the UK's statutory welfare code, not a guess.

🇬🇧 UK version/🇺🇸 US version

Standards usedSchedule 8 legal minimumRSPCA Assured standard

Number of pigs

Average weight (kg)

Housing type

Legal minimum floor area

1.60 m²

0.40 m² per pig × 4 pigs

Feed cost calculator · Water calculator · Bedding calculator · Cost of keeping calculator

RSPCA Assured standard

1.88 m²

of which 1.24 m² must be dry, bedded lying area

Keeping pigs as pets? The RSPCA’s advice for pet pigs is “a minimum area of 36 square metres (6 x 6 metres) per pig (ideally a larger space)”. It’s advice for pet keepers rather than a farm standard, and its wording doesn’t say whether that means the dry lying area or the total area per pig, so it isn’t one of the results above. Read how the figures compare.

What this means

A roughly square pen would be about 1.3m × 1.3m. Long, narrow runs work too.

If you’re building a rectangular pen, examples include: 1.3m × 1.3m, 0.9m × 1.7m, 0.7m × 2.3m.

Working backwards: how many pigs fit?

Floor area you have (m²)

Figures apply to England. Legal minimums are from Schedule 8 of the Welfare of Farmed Animals (England) Regulations 2007. Higher-welfare figures are from the RSPCA welfare standards for pigs, which apply to RSPCA Assured members; the RSPCA has stated it intends to increase these allowances in a future revision. Both are group allowances — a per-head share of a larger pen — so for one or two pigs they can work out smaller than the pig itself. Where that happens we show our own estimate of the smallest pen a pig can be kept in (roughly the square of its length, an interim reading of Schedule 8 para 6) and say so; it is a bare minimum, not a recommended size. Scotland, Wales and Northern Ireland have their own regulations. This tool is a planning guide, not legal advice — check current rules before building.

How we calculated this +

Legal minimum floor area

Source:: Schedule 8, Welfare of Farmed Animals (England) Regulations 2007
Applies to:: England — statutory minimum
Assumption:: Bands are a per-head share of a group pen by average group weight, not an individual-pig figure.
Calculation:: Average weight looked up against the published bands (0.15m² under 10kg, rising to 1.0m² over 110kg), multiplied by pig count.

RSPCA Assured standard

Source:: RSPCA standards justification (pigs), 2024
Applies to:: England — RSPCA Assured members
Assumption:: Published as point weights, not bands — rounded up to the next published weight (the conservative reading). Held flat above 110kg pending a published figure for heavier pigs.
Calculation:: Weight looked up against the indoor or outdoor RSPCA table, giving a total shelter figure and a dry, bedded-lying-area sub-figure, each multiplied by pig count.

Paddock land (outdoor)

Source:: RSPCA standards justification (pigs) — free-range labelling, Section E9.3.3
Applies to:: England — RSPCA Assured free-range labelling standard
Assumption:: Flat per-head figure regardless of weight; differs only by whether pigs are rotated to fresh ground or kept on the same ground.
Calculation:: 12m²/pig (rotated) or 40m²/pig (static ground), multiplied by pig count. This is land, not shelter — the RSPCA shelter figure above still applies on top of it.

Small-group practical floor area

Source:: Allometric body-area scaling, applied to Schedule 8 para 6
Applies to:: England and the US alike — a pig's body size isn't jurisdiction-specific
Assumption:: Our calculated planning figure — not a statutory or RSPCA requirement. It's the one figure on this page not taken directly from a published table, shown here rather than presented as equally authoritative. It is roughly the square of the pig's length — an interim approximation of Schedule 8 para 6's rule for a pig kept on its own, pending a citable length-by-weight table. A bare minimum, not a recommended or comfortable pen size.
Calculation:: Floor area ≈ 0.041 × weight(kg)^0.67 × 1.6 clearance factor. Applied to the pen as a whole, so it only changes the result for very small groups (roughly 1–3 pigs), where the group-allowance figures above would otherwise produce a pen smaller than the animal.

Why there's no third "planning figure" here

Source:: DEFRA, Code of Practice for the Welfare of Pigs (2023), paragraph 163; RSPCA, "Environment for pigs" (pet pig advice)
Applies to:: England
Assumption:: DEFRA's Code says housing design and management "may mean that greater space allowances are necessary" than the legal minimum, but publishes no number. The RSPCA's advice for pet pig keepers does: "a minimum area of 36 square metres (6 x 6 metres) per pig (ideally a larger space)". That is written for pet keepers rather than as a farm standard, and the wording doesn't say whether it means the covered lying area or the total area per pig, so it isn't clear it can be compared directly with the figures above.
Calculation:: No calculation. We don't invent a multiplier to fill the gap between the legal minimum and RSPCA Assured — a mistake this site made once already and corrected — and we don't present the RSPCA pet-pig figure as a third tier until its meaning is clear. It is discussed in the guide on how much space a pig needs.

Sources checked: September 2026.

Rules can depend on where you live. National welfare requirements aren't the same thing as local planning, registration, nuisance or disease-control rules — check with your local authority before you build or buy.

What this means

The first figure is a legal minimum, not a target. Schedule 8 sets space by average group weight — from 0.15m² per piglet under 10kg up to 1m² per pig over 110kg — and RSPCA Assured, a genuine higher-welfare certification scheme, asks for more. Outdoors, paddock land is a separate figure from shelter: 12m² per pig where the ground is rotated, 40m² where it isn't.

Because the published tables are a per-head share of a larger group pen, for one or two pigs they can work out smaller than the pig itself. Where that happens we show our own estimate of the smallest pen a pig can be kept in, and label it as ours — a bare minimum, not a recommended size.

Technical methodology +

The source, assumption and arithmetic behind every figure are in “How we calculated this” above, and collected for all the pig figures on the Sources & methodology page.

Sources checked: September 2026.

Common questions

Are these legal minimums or recommended sizes?: The first figure is the legal minimum under Schedule 8 — an absolute floor, not a target. The second, RSPCA Assured, is a genuine higher-welfare certification scheme. DEFRA's Code of Practice for the Welfare of Pigs says more space may be needed but doesn't publish a number. The RSPCA's separate advice for people keeping pigs as pets does give one — a minimum of 36 square metres per pig, ideally more — but it is pet-keeper advice rather than a farm standard and its wording doesn't say whether that means covered or total area. The calculator shows only the two figures with a published standard behind them; our space guide discusses the RSPCA advice.
Does a pig's weight affect how much space it needs?: Yes. Both the legal minimum and the RSPCA standard scale with average group weight — from 0.15m² for piglets under 10kg up to 1m² for pigs over 110kg under Schedule 8. Heavier pigs need more space per head, not just more total space for more pigs.
Can two pigs share a pen?: Yes — pigs are social animals and are almost always kept in groups rather than singly. The figures above are already group allowances (a per-head share of a shared pen), which is how Schedule 8 and RSPCA Assured expect pigs to be housed.
Does the calculator include outdoor space separately from indoor shelter?: Yes, if you select outdoor housing. Paddock land (12m² per pig rotated to fresh ground, or 40m² per pig on static ground) is a separate figure from the shelter or ark size — free-range pigs need both, not one or the other.
Does this apply if I only keep a couple of pigs?: Yes. The per-pig space requirements in Schedule 8 apply regardless of how many pigs you keep — there's no small-holding exemption from the space standards themselves.
What if my pigs are different weights?: Use the average weight of the group. If there's a wide spread, it's safer to size the pen for your heaviest pigs.
Is there a version of this for the US?: Yes — see our US pig pen size calculator, based on the National Pork Board's standard.

You might also need

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