But how does the fare work, where does it apply and will it actually save Londoners money on their commute?
Here is what you need to know about the new change across the capital.
How does it work?
The ticket allows two journeys within 60 minutes and only charges £1.50 in total.
So if you get on a bus and choose to switch buses within the hour, it will only charge you for one bus journey.
Do I need an oyster card for it to apply?
No, it can be a pay as you go oyster card or contactless payment
Does it work for people with weekly monthly or seasonal oyster cards?
The changes only apply to those with a pay-as-you-go oyster card
How many people will benefit from the fare change?
City hall have estimated nearly 90 million people will benefit from the new scheme, many of whom get two buses within the hour, particularly in south London.
Why isn't it unlimited travel for one hour?
Limited to two journeys only, Sadiq Khan said the reason for this was because original plans to include unlimited one hour travel were deemed not possible by Transport for London (TfL) until they upgrade their ticketing systems next year.
A spokesperson for TfL said: "In 2018, possibly sooner, passengers will be able to make unlimited bus transfers within one hour after TfL has upgraded its ticketing technology."