Video report by Bruce McKenzie.
The Ethical Dairy, near Gatehouse-of-Fleet, says the certification required to send single parcels of its craft cheeses to individual customers over the Irish Sea is on a par with that of entire containers of ice cream its sister company has sent to South Korea.
Wilma Finlay, who founded the firm alongside husband David, told ITV Border News the costs involved under the new post-Brexit regime don't stack up.
She said: "For our average customer order worth £33, looking at the costs where we'll get an invoice in and the time involved, we're looking at around £45 (to complete the necessary paperwork) and that's before you factor in the cost of producing the cheese."
The firm would have to produce animal health certificates, documentation for organic equivalence and customs forms despite the fact Northern Ireland is less than fifty miles away from its farm.
The Prime Minister's spokesman said: "The Northern Ireland Protocol agreed with the EU delivered on our commitment to make sure Northern Ireland has unfettered access to the rest of the UK market.
"Since the start of January there has remained a good flow of trade between the UK and Northern Ireland.
"The Trader Support Service is processing 99% of declarations within 15 minutes, and answering most calls within 30 seconds."
But Mrs Finlay claimed says that small firms supplying small deliveries have been forgotten and would suffer unless the system was reconsidered, "We are not unfamiliar with exporting.
"Ten years ago we exported ice cream from our sister company, Cream o’ Galloway, to South Korea and the export paperwork required to do this was similar.
"The difference is the scale. Vet certificates and export paperwork are justifiable to enable export of a shipping container of ice cream.
"It simply isn’t justifiable, from a business point of view, to do this for an individual order of cheese".