That is one in every 50 - so make sure you check what's in your pocket.
The number of counterfeit coins have doubled in just five years.
So here's your guide to find out if your pound coin is worth its weight - or just worthless.
The key things to look for are:
-Indistinct lettering or wrong typeface on edge
-Queen's head and pattern on reverse should both be upright when coin is turned over
-Design on reverse should correspond with official design for year of its issue
Also, the Latin motto on the edge of the coin should also correspond to the right year.
And vending machines regularly reject suspect coins - it's not always the machine that's at fault!
Overall, dodgy coins can easily be spotted by the untrained eye.
Compare the Queen faces on the coins and see how different they are.
The chances are you will come across a fake one sooner or later.
Do you have a fake pound coin? Let us know by clicking here.