The Farmers Union of Wales (FUW) has said new business rates will 'cripple' rural businesses.
From April 2017, many businesses will see their business rates increase dramatically.
FUW has called on Chancellor Philip Hammond to use his budget next month to reduce the 'huge' increases.
The last time rates were set was seven years ago, but property price changes since then have led to big winners and losers.
Rates will fall for 920,000 businesses, remain the same for another 420,000, and increase for 510,000 across the UK.
Under the current scheme, business premises with a rateable value of up to £6,000 will receive 100% relief and those with a rateable value between £6,001 and £12,000 will receive relief on a tapered basis from 100% to zero.
'Threatening viability'
To highlight the point, FUW has met with MP Liz Saville Roberts to discuss the increases, how business rates are set, and that the basis for the rates can differentiate between businesses.
FUW Meirionnydd County Executive Officer Huw Jones said: “It will also have a devastating effect across Wales and our rural communities. Some businesses are seeing hykes of £15,000 or more, threatening their viability.”
FUW Head of Policy Dr Nick Fenwick, said: “We have written to the Chancellor to highlight the extreme impact these changes will have on large numbers of businesses, but we would also urge businesses to contact their MPs and AMs.
“Many farm businesses which have tried to make up for falls in income by diversifying are now seeing their efforts wiped out by this rise.”
The Countryside Alliance has also called for a re-think of the rates, saying the Government should go 'go back to drawing board' over 'punitive' rate rises that risk damaging rural businesses.
