You could be fined £500 from today if you haven't had your dog microchipped. The tiny device means an owner can be traced if they go missing.
The law now states that every dog must be chipped by the time they are eight weeks old.
Just over half of dogs in the UK are currently microchipped, however the Government says stray animals cost councils and charities millions of pounds every year.
At Highgate Vets in Kendal staff say the new law will make it easier for them to help injured or lost dogs.
As a nation of dog lovers, back in 1932 everyone rushed to get their pet license and it's hoped there'll be a similar response to microchipping.
But the good news now is that if your dog is found without a chip, you'll have 3 weeks to get it done before you're fined £500.