What is classed as a large letter royal mail

According to Royal Mail's guidelines, a large letter is defined as a letter that measures more than 240mm (9.5 inches) in length, width, or thickness. This includes letters that are:

Examples of items that may be classified as large letters include:

It's worth noting that Royal Mail has specific rules and restrictions for sending large letters, including:

If you're unsure whether your letter is considered large, it's always best to check with Royal Mail or consult their website for more information.