Paper car tax discs no longer exist but if you've got one still stuck to the windscreen of an older vehicle or tucked among some outdated paperwork it could earn you a fortune.

The circular paper badges, which proved vehicle tax had been paid, have become collectors items in recent years with some now fetching hundreds of pounds via online selling sites.

Car tax discs were first introduced exactly a century ago in 1921.

But they were phased out by the government in 2014 when a move was made towards a more digital way of registering and tracking vehicle tax payments.

Old car tax discs now change hands just like stamps and other small collectables, with 'velologists' the name given to people who collect old discs, alongside entire websites dedicated to their pursuit.

'Very rare' tax discs can now be found for sale online with some attracting the attention of numerous bidders. Among the most collectable are 100-year old tax discs dating back to January 1921 when the very first documents were introduced.

One particular tax disc from 1921, with an expiry date of December 1923, is up for grabs with one seller who is seeking a minimum of £300 for it.

Car tax discs which still have their borders or margins around the circular edge are thought to be the most valuable along with - as with any collectable item- those in peak condition despite their age. Early discs, which came with no perforations - and so had to be cut away from their attached paperwork - can have their value affected if their original owner wasn't so neat and tidy with the scissors.

Collectors there say the value of old car discs is now at an an 'all time high' with some extremely rare expired papers able to fetch £1,000 or more.

Some online sellers are trading larger sets of car tax discs spanning specific years - for example an entire collection from the 1940s or tax discs from consecutive decades. These are currently fetching higher sums of money because, according to official website Velology, they are becoming harder to get hold of.

On Ebay a series of 13 tax discs from 2003 until 2015, which would include one of the final discs ever to have been issued before the documentation was phased out completely, are currently for sale for £250 for the set - while just one 1951 disc bought for a Ford car 70 years ago is likely to fetch at least £20 for its current owner.

Despite the five to six year gap since the last paper versions were officially issued there is still considerable interest among petrol heads and car enthusiasts in the old motoring documentation says car company Lease Car UK.

A spokesman explained: "Many people find it fascinating to explore buying and selling websites to look at the variety of used car tax discs that are available today.

"These small round pieces of paper are an important part of our motoring heritage and it is particularly poignant that on the 100th anniversary of their introduction on our roads that car tax discs from as early as the 1920s are actively available to buy."

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