So it turns out the new plastic fivers aren't entirely vegan friendly and it's come as a shock to a lot of people.
Twitter user Steffi Rox asked the Bank of England on Twitter whether the much raved about notes contain tallow - a hard substance which is made from rendered animal fat that has long been used in the making of things like soap and candles.
And the Bank's official account replied directly confirming they do contain a "trace" of the product.
Lots of people are completely baffled why this kind of thing is still being used in this day and age.
Many were horrified.
And a petition has even been launched to get the Bank to remove the tallow.
But some aren't too fussed and are offering to take the unwanted money off people's hands.