The budget retailer will be replacing green caps with clear caps on semi-skimmed and organic fresh milk.
Red tops and blue tops - used to indicate skimmed and whole milk - won't be included in the trial.
The change will start to be rolled out from today (October 31) and will be available in all stores by November 21.
Lidl says the new clear caps are more environmentally friendly than the old green caps, as they will be recycled to create milk bottles.
It is estimated that 60 tonnes of recycled High-Density Polythene per year will be turned back into food-grade packaging as a result.
It follows a successful four-week trial with Müller earlier this year.
Scott Davey, Senior Buying Director said: “We remain committed to supporting our customers in helping them make more sustainable shopping decisions on a daily basis.
“Customer feedback during the trial was overwhelmingly positive and we are thrilled to be making this change permanent across Lidl stores.
“In addition, this move will help us achieve our goal of making more of the plastic we use circular and fit to be repurposed time and time again.”
Lidl isn't the only one to confirm a huge change to how it sells milk.
Waitrose was the first to confirm it was ditching coloured tops in favour of clear ones - also in collaboration with Müller - in June.
The posh supermarket has scrapped red, blue and green milk bottle tops
Aldi also confirmed it will switching to clear lids instead of green tops in August, as part of a trial across stores in Cheshire, Manchester and Liverpool.
The retailer is instead putting "best before" dates on 90% of its own-brand milk and will encourage customers to use a sniff test to check quality.
Muller Milk & Ingredients commercial director Liam McNamara said: “Everyone is thinking more about what they buy, the nutritional benefits, the value it represents and the packaging used.
“We want to be the partner of choice for our customers, we recognise the commitments they are making in this area, and following a successful trial period, then this is another step we can offer.“