If you are more than 3 hours late you must:

• Take the one you missed as soon as possible. You can take 2 pills at the same time or on the same day.
• Keep taking the pills as usual, 1 each day.
• Use emergency contraception if you've had sex in the last 5 days as sperm can live that long inside the body!

Also read the instructions you get in the box carefully should you miss a pill!