A3 postage cost royal mail

According to the Royal Mail website, the postage cost for a standard A3 letter or document is as follows:

• 1st Class Large Letter (A3): £1.15
• 2nd Class Large Letter (A3): £0.85

Please note that these prices are subject to change, so it's always best to check the Royal Mail website for the most up-to-date pricing information.

Additionally, if you're sending a larger or heavier item, you may need to use a different service, such as a parcel or packet, which would have a different postage cost.