An 11-year-old British boy plugged his Samsung tablet into a charger overnight — and awoke to find it had burned a rectangular hole in his mattress down to the springs, according to a report.

The electrifying incident happened after the kid, from Staffordshire, plugged the 4-year-old gadget into its original charger around 9 p.m. Wednesday, local fire officials told the Manchester Evening News.

The device overheated and scorched his mattress, covering his bedroom with a layer of black soot — but the boy managed to walk away unharmed, according to the paper.

The kid’s family is lucky a blaze didn’t break out in the home, a Lichfield Community Fire Station chief told the outlet.

After the smoldering tablet was found, the fire department urged folks not to leave electronic devices charging on potentially flammable surfaces.

“Always place phones and tablets on to a safe surface when charging,” the department said in a statement. “Make sure you buy genuine chargers for your items and follow the manufacturer’s instructions.”

A rep for Samsung didn’t immediately return The Post’s request for comment.