Okay, let’s get the dull stuff out of the way so you can plan your next escape. Your card works on all TfL services within the London fare zones, plus all National Rail stations within those zones. But if you go outside the zones—say, to Reading or Southend—you’ll need to pay for the part beyond the boundary. It’s like a free slice of cake, but you pay for the extra icing. Check the TfL map online before you set off; it’s not rocket science.
One-third of older Londoners say the capital is ‘unaffordable’ | Inside
Also, don’t try to use it before 9:30 AM on weekdays. You will get slapped with a penalty fare. I saw a guy get caught at Fenchurch Street once. He tried the “I didn’t know” defense. The inspector just smiled and handed him a £50 bill. Don’t be that guy.