Miranda Lambert has donated money to an animal shelter.

The 35-year-old country star has reported gifted ''a few thousand dollars'' to Scituate Animal Shelter in Plymouth County, Massachusetts, as part of a surprise donation.

The exact amount Miranda donated has not been revealed, but the shelter's executive direction Maryann Regan has told TMZ that the money has allowed the company to temporarily waive adoption fees, allowing people to take home an animal pal for free.

According to TMZ, the limited free scheme - which is running until July 19 - has encouraged a boost to business with ''a lot more people'' visiting the shelter ''to find pets'' and give the animals a new home.

Maryann first discovered the donation made my Miranda back in March, when she was going through her mail and found a letter and certificate personally signed by the 'House That Built Me' singer.

The letter was sent from Miranda's non-profit organisation MuttNation Foundation, which she founded alongside her mother 10 years ago with the aim of helping to promote the adoption of shelter animals.

The foundation often donates money and other resources to well-run shelters, and Scituate is a first-time recipient of the scheme.

Maryann says she decided to hold off on using the donation until the summer, as this is when the shelter is the most packed.

The shelter is now tripling their usual rate of adoption over the summer - which is often only two animals a day - with the donation helping to eliminate the adoption fees which normally cost between $100 and $250.

Meanwhile, Miranda's charity previously rescued domesticated animals left alone in the wake of Hurricane Harvey, which struck Houston, Texas, in 2017.

The charity helped over 200 animals by helping to find them food and shelter until attempts could be made to reunite them with their owners.