The secrets in your passport

The secrets in your passport

HOTEL room cards can be a pain in the neck for holiday-makers: if you leave the room and take the key from the slot, the electricity cuts out.

But it turns out that the dilemma of how to keep your phone charging or whether to leave your other half snoozing without access to light was completely unnecessary.

Because the slot for the keycard will take any card — not just your room key.

Londoner Katyagar Moonagon revealed her discovery on Twitter, The Sun reports.

“[I] wanted to charge my battery pack whilst I was I eating dinner, but needed my keycard,” she said.

She then posted a picture of her supermarket loyalty card in the slot instead, and said it did the trick.

Wanted to charge my battery pack whilst I was I eating dinner, but needed my keycard pic.twitter.com/TsHqihGxTu — katyagar moonagon (@Oog) March 14, 2018

“I turned off all the lights manually, as not to be too wasteful, just needed to bump up the old battery pack for an hour or two,” she said.

The picture has already been re-tweeted hundreds of times, with some people calling the revelation life-changing.

Fellow Londoner Suzanne Azzopardi said: “I’m 42 and didn’t know you could put any card in the bloody hotel light thingy.”

Even hotel works were amazed by the trick.

“I’m dumbfounded. I worked in 5 Star Hotels and never came across that,” Twitter user Ronan Alex Dunne said.

Another genius hotel trick shared on the internet is how useful a cheap doorstop can be when travelling.

The simple rubber stop can be used while staying at every hotel room to stop unwanted intruders from breaking and entering.

This article originally appeared onThe Sun and was reproduced with permission.