The dairy coalition is gathering evidence on processor compliance with the dairy voluntary code of practice ahead of the annual review in autumn.
The NFU has written to every single milk buyer registered with the Rural Payments Agency asking them what they are doing in relation to the code and what their thoughts are on the code for the future.
"While we are pleased with achieving in excess of 85% compliance with the code, in terms of milk volume, we know a number of smaller milk buyers are yet to offer farmers compliant contracts," said NFU chief dairy adviser Rob Newbery.
"With the review expected to take place this autumn and farmers looking for clear information about processors who they are or may in the future be doing business with, it is important to have clear information in the public domain."
The coalition wanted to move past the "name and shame" phase, said Mr Newbery, who urged any farmers to get in touch if they felt their processor was falsely claiming they didn't need to adhere to a part of the code because it was something their farmers said they didn't want.
"At the end of the day, if milk buyers believe the contracts they offer are what farmers want, then they should have no problem being open about this."
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