UK agriculture spent £1.8 billion on fertiliser in 2025 — £92 million more than the year before, up 5.5%. Ammonium nitrate averaged £385 a tonne against £338 in 2024. That is £47 a tonne more; on a twenty-tonne load, near enough £940 you did not spend last year for the same delivery.
The numbers come from Agriculture in the United Kingdom 2025, Defra's yearly round-up of the industry, published in July and updated at the start of September. It runs to 195 pages, so we have pulled out the fertiliser part — and then done the bit Defra does not do, which is turn it into pounds per hectare.
The bill went up; the tonnage probably did not
This is the part worth understanding. Defra attributes the increase to farmers changing their buying patterns in response to price, rather than putting on more product. The fertiliser and soil improvers price index rose from 154.1 to 170.8 — up 10.8% on the year, with 2020 set at 100.
So the extra £92 million is not more nitrogen going on the ground. It is the same job costing more. Defra points at gas prices as the reason — natural gas is the bulk of the cost of making nitrogen fertiliser — along with lower domestic production and tight global supply.
For what it is worth, it is still not 2023, when ammonium nitrate averaged £453 a tonne. We are well under that, even after this year's climb.
Turning £385 a tonne into pounds per hectare
A price per tonne is hard to feel. A cost per hectare is not, and the sum is easier than you might expect.
Ammonium nitrate is 34.5% nitrogen, so a tonne of it carries 345 kg of N. That gives you something you can work out on the back of the delivery note:
Cost per hectare = your nitrogen rate (kg N/ha) ÷ 345 × the price per tonne
If you are not on straight AN, swap the 345 for your own product: a tonne carries the percentage of nitrogen times ten. Urea at 46% is 460 kg of N per tonne; CAN at 27% is 270.
So where does the nitrogen rate come from?
From the recommendation tables — and this is where your own ground enters the calculation, because soil type decides the number twice over.
First it helps set your Soil Nitrogen Supply index. You either measure it, by sampling for soil mineral nitrogen down to 90 cm, or you look it up from your previous crop, your soil type and your rainfall area. Then the SNS index and the soil type together pick the rate. For wheat sown up to the end of January, at SNS Index 1, the published rates and what they cost at this year's £385 a tonne look like this:
| Soil type | kg N/ha at SNS Index 1 | Cost per hectare at £385/t |
|---|---|---|
| Organic soils | 80 | £89 |
| Light sand soils | 150 | £167 |
| Deep silty soils | 210 | £234 |
| Medium soils | 220 | £246 |
| Deep clay soils | 220 | £246 |
| Shallow soils | 240 | £268 |
Nitrogen rates: Source: AHDB Nutrient Management Guide (RB209), Section 4, Table 4.15. Costs per hectare are our own arithmetic using the Defra price.
Same index, same crop, same year — and £179 a hectare between the top and the bottom of that column, decided by nothing but the soil under the crop. There is a yield adjustment on top: the table assumes 8 t/ha, and RB209 allows 10 kg N either way for every half tonne you consistently make above or below that, up to 13 t/ha.
Take the medium-soil line as a worked example. 220 kg N ÷ 345 × £385 comes out at about £246 a hectare. At last year's £338 the same 220 kg cost about £216. Call it £30 a hectare more for putting on precisely the same nitrogen — around £3,000 across 100 hectares of wheat, with nothing extra in the ground to show for it.
What the national average is good for, and what it isn't
The UK has roughly 17 million hectares of utilised agricultural area across about 212,000 holdings. Spread £1.8 billion over all of it and you get about £106 a hectare.
We will be honest with you: as a benchmark that number is close to useless, and we would rather say so than dress it up. It mixes intensively fertilised cereal ground with rough grazing that never sees a bag — you have just seen the same crop range from £89 to £268 a hectare on soil type alone. What it is good for is scale: it tells you what the industry as a whole hands over in a year.
The rest of the input bill
Fertiliser was the outlier. Total intermediate consumption — everything farms buy in to produce with — came to £21.6 billion, up £331 million or 1.6%. Underneath that:
- Animal feed — £7.1 billion, down £32 million (0.4%)
- Energy — £1.9 billion, down £41 million (2.1%)
- Seeds — £1.0 billion, up £22 million (2.2%)
- Plant protection products — £925 million, down £39 million (4.0%)
Most inputs held steady or eased. Fertiliser went the other way.
Doing the sum on your own fields
Everything above is arithmetic you can do yourself, and the point of showing it is that you can check it rather than take our word for it. If you would rather not page through the tables, our lime calculator works the same way for pH, and our nutrient recommendation tool does the nitrogen, phosphate and potash side — it is offline at the moment while we complete a licence agreement with AHDB, and it will be back.
If it is the machinery side of the bill you are weighing up, our page on what precision farming actually costs in the UK covers that ground.
Where these figures come from
- AUK 2025, Chapter 9: Intermediate consumption — fertiliser, feed, energy, plant protection, seeds and the total.
- AUK 2025, Chapter 6: Prices — the price index, ammonium nitrate per tonne, and the 2023 comparison.
- AUK 2025, Chapter 2: Structure of industry — agricultural area and number of holdings.
- AHDB Nutrient Management Guide (RB209), Section 4, Table 4.15 — nitrogen rates for wheat, the yield adjustment and the nitrogen content of fertiliser products.
This is a summary of published figures, not advice. Defra statistics are used under the Open Government Licence; RB209 is the intellectual property of the Agriculture and Horticulture Development Board and is reproduced here with attribution.