For the past 31 years, the European Union has had quotas, or limits, on how much milk farmers can produce.
The rules were put in place so farmers wouldn't make too much but would also get a fair price.
But now those quotas have been lifted so with no limits farmers are being allowed to produce as much milk as they want.
Four farmers got in touch with Newsbeat to tell us how they'll be affected by the changes.
"We've all known this has been coming for some time. We've been trying to put our businesses in the best possible position - to produce milk as cheaply as possible.
"This means keeping as many cows and pushing out as much milk as we can for every worker, as well as producing as much milk as possible from grass - the cheapest feed available on our farm.
"It's likely that this will lead to a flood of milk and probably pull down the price even further.
"It's not an easy game and it never will be. I suppose, really and truly, the most efficient farms will survive the test of milk quota removal.
"It'll be a survival of the fittest."
"I'm from a family farm and we've mixed feelings about the end of the quotas as it leaves the dairy industry in an unknown area.
"You don't know how the markets are going to evolve with the access to more products from Europe and also allowing farmers within the UK to expand.
"Usually in the spring time, that's when the cows get [put] to grass, and you get an increase in milk production.
"So if you're lifting the quotas at the same time, you're going to have a lot of milk in the country and not necessarily be getting a very good price for it."
"I think pretty much everyone is aware that milk prices aren't great, which means farmers are losing money.
"It's heartbreaking when you see people leaving the industry. It sounds silly, but cows become a part of your family and to face the prospect of walking into an empty farmyard is something none of us want.
"The removing of quotas is potentially a great opportunity for famers to move into the global market. It's all down to how you see it, do you view it an opportunity? Or do you see it as a time to quit? Some people see it that way, but I hope that doesn't put young farmers off."
"The milk price at the minute is devastating small farmers like myself, simply because you physically can't afford to carry on really.
"It's going to get to the point where there's only going to be these so-called super farms left, with 1,000-2,000 cows or in some cases even more.
"My parents are just barely scraping by to keep the household going.
"Dairy farming's hard - you're doing 12-13 hours days every day. It's not a job, it's a way of life and we love it.
"It's a valuable part of the English countryside and it just seems to be fading away.
"It just seems sad that it might come to the point where we might have to give it up."
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Dairy farmers work hard to help get things like milk, cheese and butter from the farm and into our kitchens.