Royal Mail customers are advised to write two important words on every parcel or letter they send. The postal service provides advice on its website to help customers ensure their mail reaches its destination as quickly as possible.
The advice includes tips on how to address an envelope so it can be delivered to the right place. Customers are also asked to add a return address to anything they send in the post, in case the item can't be delivered.
As Royal Mail's website explains, all customers should write 'return address' on the back of the envelope, followed by their information. Taking a few seconds to add the information could be vital if there's an unexpected issue during delivery.
The postal service said: "If for any reason your item can't be delivered, we can send it back to you. Write the words 'return address' on the back of the envelope and underneath that, the actual return address." In the illustrative photo shared alongside the advice, Royal Mail wrote the return address on the bottom right of the envelope.
Customers should make sure that both the send and return addresses are clearly visible and easy to read. Royal Mail said: "It's important that the address shows up against the colour of your envelope."
If customers are using a coloured envelope, it could be helpful to use a white label on the address side. Royal Mail suggests using black ink. Royal Mail's website also explains how to address the envelope, providing specific guidance for different countries, as the required format may vary.
Generally, Royal Mail said the top line should be the recipient's full name. The middle lines are used for the person's specific address.
Royal Mail explained: "Use a line for the property number and street name. If the property has a full name, this can take up one line and drop the street name onto the next line.
"On the following line, you can put the name of the local area or village name. Next, write the name of the town in capital letters. You don't need to include a county name, as your letters and parcels will still reach the right place. However, you can include it if you prefer."
Finally, the bottom line should be the UK postcode or information about the international destination. Royal Mail said: "UK destination: The final line should be the UK postcode, again in capital letters. International destination: After the area code, add the country name to the final line, again in capital letters."