Square Meters to Acres

Reading a Registered Parcel Area in Acres

A title register, a cadastral extract or a surveyor's plan states the parcel in square metres. The buyer, the agent and quite often the contract talk in acres. Somewhere in the file that same piece of ground has to be described both ways without the two versions contradicting each other — and a conveyancer is the person who has to make the numbers agree.

Conversion factor: 1 m² = 0.000247105381 ac, because an acre is defined as exactly 4 046.8564224 m². A register entry of 1 011.714 m² is precisely 0.25 ac — the old quarter-acre, still one rood in the language of the original deed.

Why Registers and Contracts Disagree on Units

Registries record in metric

Land registries across the UK, Ireland, the EU, India, Kenya and most of Africa and Asia hold parcel areas in square metres or hectares, computed from digital mapping. The acre survives in conversation and marketing, not in the index.

General boundaries, not surveyed lines

Under the general boundaries rule an English title plan shows roughly where a boundary runs, not its exact legal line. The area that follows from it is an approximation carried to a convenient number of digits.

Older deeds count in roods and perches

Pre-decimal conveyances are written in acres, roods and perches: 4 roods to the acre, 40 perches to the rood. A rood is 1 011.7141056 m² and a perch 25.29285264 m², so an antique recital converts exactly.

Buyers still negotiate in acres

Price per acre is how agricultural land, paddocks and rural plots trade in the US, UK, Ireland and much of the Commonwealth, so a metric register figure has to be restated before anyone can compare an asking price.

From the Title Plan to the Contract Figure

The discipline that keeps a file clean is to convert the recorded number once, decide the precision deliberately, and use that one acre figure everywhere it appears.

Type the area exactly as recorded

Enter the square metres from the register or survey plan, digit for digit, including any decimals it carries. Spaces in a grouped figure are ignored and a comma is read as a decimal separator, so a continental extract can be typed as printed.

Choose the precision the document deserves

One hundredth of an acre is 40.47 m² — a whole garden. One ten-thousandth is 0.40 m². Town plots need four decimal places to stay honest; a farm sold by the acre rarely needs more than two.

Copy it into the schedule or the listing

The copy button lifts the bare number without unit or grouping, ready to drop into a schedule of parcels, a sales particular or a valuation sheet. Ctrl + C inside a field does the same.

Reverse it to audit a stated acreage

When the particulars claim "about 2 acres", press the swap button (↔) and run acres to square metres: 2 ac is 8 093.71 m². If the register says 7 100 m², the advertisement is 12 % optimistic and worth raising before exchange.

An area is a description, not a warranty: registered and plan areas are commonly stated for identification only, and a converted acre figure inherits every uncertainty of the mapping it came from. Never let a conversion become the operative description of what is being sold.

Registered Parcel Sizes and Their Acre Equivalents

Typical parcels as a registry would record them, alongside the hectare and acre figures the same land is discussed in.

Parcel	As recorded (m²)	Hectares	Acres
Terraced-house plot	120 m²	0.0120 ha	0.0297 ac
Semi-detached plot	250 m²	0.0250 ha	0.0618 ac
Detached suburban plot	500 m²	0.0500 ha	0.1236 ac
Eighth-acre residential plot	505.857 m²	0.0506 ha	0.1250 ac
Quarter acre (one rood)	1 011.714 m²	0.1012 ha	0.2500 ac
Paddock or smallholding	4 046.856 m²	0.4047 ha	1.0000 ac
One-hectare enclosure	10 000 m²	1.0000 ha	2.4711 ac

Notice how few of the round metric numbers land on round acres. Only the parcels that were laid out in imperial measure — the rood, the eighth-acre plot common in Kenyan and Irish subdivisions — convert to clean fractions, which is itself a clue about when a boundary was first drawn.

What Matters When Checking a Title

Run a schedule of parcels in one pass

Both fields stay editable, so a register with eleven numbered parcels can be worked straight down the list without resetting anything between entries.

Audit an advertised acreage

Reversing the direction turns a claimed acre figure back into square metres you can hold against the register entry before raising an enquiry.

The rood and the are are in the list

The searchable dropdowns include the rood and the are as well as hectares, so an old conveyance recital can be checked against a modern register without a second tool.

Digits fine enough for a small plot

Results run to eight decimal places, which keeps a 120 m² town garden meaningful in acres instead of collapsing to 0.03 and losing a third of the plot.

Title, Deed and Boundary Area Questions

Why does my title register give the area in square metres and not acres?

Because the register is computed from national mapping that has been metric for decades. Registries derive the figure from the digitised parcel polygon, and the polygon's coordinates are metres. The acre never enters the calculation, so quoting it would mean the registry doing a conversion on your behalf and taking responsibility for the rounding.

Is the area on a title plan a guarantee of where the boundary runs?

No. In England and Wales the general boundaries rule means the red line shows the boundary's general position only; the exact line is undetermined unless someone has applied to have it fixed. At 1:1250 mapping a plotted line half a millimetre wide already covers about 0.6 m on the ground, which on a 20 m frontage is roughly 12 m² — some 0.003 ac of doubt before anything is disputed.

How many decimal places should an acre figure carry in a contract?

Match the precision of the source. Two decimals of an acre is a step of 40.47 m², fine for a 40-acre farm and useless for a garden; three decimals is 4.05 m²; four is 0.40 m². For a residential plot recorded to the whole square metre, four decimals reproduces the register faithfully and does not invent accuracy nobody measured.

My old deed says "3 acres, 2 roods and 20 perches" — what is that today?

3.625 acres, or 14 669.85 m². Two roods is half an acre and 20 perches is half a rood, so the recital reads 3 + 0.5 + 0.125. Multiplying 3.625 by 4 046.8564224 gives 14 669.8545 m², about 1.467 ha — a useful check that a modern register entry really covers the land the old conveyance described.

The surveyor's plan and the register give different square metres — which goes in the contract?

Neither, as a promise. A measured survey computed from coordinates is more exact than an area read off general-boundary mapping, and a small difference between them is normal rather than evidence of encroachment. Describe the land by the plan and the parcel reference, state any area as approximate, and keep the survey figure in the file as the working number.