The latest figures published by DAERA show that butterfat and protein percentages in NI have increased significantly in 2026.

Our best estimate is that butterfat is likely to end 2026 at an average of 4.37%, with protein averaging 3.43%. When compared to 2025, that would represent an increase in butterfat and protein of 0.09 and 0.05 percentage points respectively – it would be the biggest annual increase in dairy constituents ever seen in NI.

As shown in Figures 1 and 2, between 2011 and 2020, minimal gains were made and over that 10-year period, average butterfat only increased from 3.99% to 4.06%, with protein rising from 3.24% to 3.30%.

However, by 2021, there were growing calls from farmers and industry consultants for a change in how processors paid their farmers. As well as properly rewarding those with good constituents, the main argument put forward was that there were efficiency gains to be had by dairy companies when processing high solids milk.

Among the co-ops, Tirlán was first to respond and from January 2022 its suppliers were on a three-year transition to an A+B-C solids-based payment (where A is the total value of butterfat, B is the value of protein and C is a cost of processing each litre of milk).

In May 2024, Lakeland Dairies announced it was giving farmers the option of switching to a similar A+B-C model, before it became compulsory across all suppliers from January 2026. Strathroy Dairies and Aurivo also give farmers the option of being paid using A+B-C.

Increments

However, for Strathroy, Aurivo, Dale Farm and Leprino Foods suppliers who remain on a traditional increment-based model, the value of each 0.01% change in butterfat and protein has significantly increased in recent years, to encourage higher solids milk.

In fact, the value now put on these increments by each processor means it would probably make more sense if everyone simplified their systems and just paid all farmers on the basis of A+B-C.

To illustrate the point, we have compared the latest prices paid by each processor for August solids (4.21% BF; 3.38% P) against what would have been paid if solids had remained the same as in July (4.13% BF; 3.34% P). As shown in Table 1 below, there is just 0.11p/l of difference across the processors. Aurivo and Strathroy are just behind the others, as their butterfat and protein increments are not as high as the likes of Dale Farm or Leprino.

Volume

Back in the late 2010s, the main argument made by those who were unsure about a switch to a solids-based payment was that it could encourage more farmers into spring calving and also result in fewer litres for dairy co-ops, as farmers would concentrate on solids over yield.

Neither has happened and the rate of growth in NI dairy output has actually increased since 2020.

Between 2011 and 2020, average yield per cow in NI rose from 7,010l to 7,809l, which works on at an average annual increase of 89l/cow. However, by 2025, average yield per cow stood at 8543l, so the annual average increase between 2020 and 2025 was 147l/cow. In other words, dairy farmers in NI have managed to significantly increase the solids content of milk since 2020, while at the same time, making big gains in yield per cow. Over the period, the average milk solids per cow has increased by 14% from 592kg to 674kg.

As well as farmers being excellent at responding to market signals, the data highlights what is possible from good feeding management, as well as breeding and genetics.

Despite the gains being made, there is still scope to do more. Data from the Netherlands shows that yields averaged 8,852l/cow in 2025, at an average of 4.5% butterfat and 3.61% protein. That works out at 739kg of milk solids per cow.

Caveat

However, there is potentially a caveat this winter relating to feed prices. For much of 2025 the milk to feed price ratio (calculated by dividing the milk price in p/l by the cost of concentrate in p/kg) was very favourable, peaking at over 1.5. As a result, cows were more likely to be fed to their potential.

However, this ratio has declined since then to currently sit below 1.1 on some farms, which is traditionally when dairy producers might think about cutting the amount of feed offered to their animals to save costs.