Self-service customers used the dodgy QR code circulated on social media.
When the digital token was scanned, a £25 Lovehoney Frisky Rabbit Vibrator flashed up on the check-out screen instead of the expected discount.
Buyers then had to plead with a member of till staff to void the unexpected sex aid.
One furious shopper blasted: “I thought I’d get a nice discount but if I knew what was on that code, I’d never have scanned it.”
Another who dodged the prank said: “So happy that people have tried the Tesco vibrator voucher thing cos I would’ve used it and been mortified.”
And employee Kelana Kirby, of Manchester, revealed: “Working at Tesco means I had at least ten people ask me to remove a vibrator from their shop yesterday.”
The pranksters had added the vibrator’s code to a screenshot of a voucher in the Tesco app.
But when The Sun tried to use the code yesterday at a Tesco store in Oxford, it was blocked by the self-checkout. Tesco confirmed it had blocked the QR code from being used.
A spokesman said: “We are aware of a fake voucher circulating on social media.
“The code doesn’t work, and we would always encourage customers to apply caution when they see claims like this online.”