Melissa Kirk/Demand Media

Large envelopes need the same basic information as small envelopes, including return and delivery addresses. Putting those addresses in the right locations on the envelope helps ensure fast and correct delivery. The post office has guidelines for large envelopes sent landscape, or with the long sides on the top and bottom, as well as portrait orientation.

What Information to Include

Melissa Kirk/Demand Media

The U.S. Postal Service requires specific address information on all letters and packages. For the delivery address, include the recipient's name, the address including suite or apartment number, the city, state and zip code. The return address includes your name and full address. The post office delivers some mail without return addresses, but some services such as Priority Mail Express require a return address. The USPS strongly recommends including a return address in all cases, including on large envelopes, in case the mail can't be delivered to the recipient or is damaged during shipping. Print the addresses clearly in capital letters or type them so they are easier for the post office to process. Avoid colored inks or cursive handwriting or fonts.

Landscape Orientation

Melissa Kirk/Demand Media

The post office prefers large envelopes to be mailed using landscape orientation. The return address goes in the top left corner, just like it does on smaller envelopes. The delivery address should start at least 1 inch to the right and 1 inch below the return address. Ideally, the delivery address should end about 1 inch from the right edge of the envelope, even if that means scooting it more than 1 inch to the right of the return address. The last line of the delivery address should be 1/2 inch or more from the envelope's bottom edge.

Portrait Orientation

Melissa Kirk/Demand Media

When you mail large envelopes with the short ends on the top and bottom, the post office prefers the delivery address to be near the top of the envelope. The return address stays in the upper left corner. Start the delivery address at least 1 inch to the right and 1 inch below the return address. Unlike landscape envelopes where the delivery address can be near the bottom, it should be as close to the top of the envelope as possible in portrait orientation while keeping the 1-inch buffer between the bottom of the return address and top of the delivery address.

Using Labels

Melissa Kirk/Demand Media

Many mailing labels suitable to use on large envelopes have spaces for both the return and delivery addresses. For some premium services, the post office requires you to use an official USPS mailing label with room for both addresses. When using a label instead of writing directly on the envelope, put the return address in the upper left corner of the label and the delivery address in the lower right section. Most labels make this easy by marking the locations with "From" and "To." If it's not marked, put the delivery address at least 1 inch to the right and 1 inch below the return address. Apply the label as straight as possible and put it where you would normally write the delivery address on the envelope.