The reminder comes just a week ahead of the introduction of contactless fares on the capital’s rail services next week.
Thousands of passengers risk being accidentally charged for their journey on a contactless credit or debit card according to a briefing document drawn up for the Mayor.
From today, fares are capped at £4.40 per day and regular users can also benefit from a Monday to Sunday cap of £20.20, the equivalent of a weekly Bus and Tram Pass.
Tube, DLR and London Overground passengers will be able to pay for their daily commute with contactless debit and credit cards from September, Transport for London have confirmed.
Contactless fares should quickly move from a handy fallback to the payment method of choice for large numbers of commuters.