Monarch envelope size

What the Monarch envelope is for

Monarch letterhead is a sheet of 7¼ × 10½ in, a little smaller than US Letter, and the Monarch envelope is made to go with it. If you order personal stationery or executive letterhead from a printer, this is usually the envelope that comes with it, in the same paper and color as the sheets.

The everyday alternative is the #10 business envelope, which is longer and a little taller because it holds a full US Letter sheet folded in three. That difference is the reason people choose Monarch: bills and statements usually arrive in a #10, so a smaller envelope on good paper reads as a personal letter before anyone opens it. You see it for thank-you letters from a company director, notes to important clients, condolence letters and private correspondence on your own stationery. For invoices and anything else printed on US Letter, the #10 remains the practical choice.

What fits inside and how to fold it

Monarch letterhead folded in three, the usual business-letter fold, comes out at 7¼ in wide and 3½ in tall. That leaves a little room on every side, so the letter slides in easily and doesn't shift around in transit. Two or three sheets folded together still fit comfortably, and so does a business card tucked into the fold.

A US Letter sheet is a different matter: it is 8½ in wide, so even folded in three it is longer than the envelope. If you have to use a Monarch for it, fold the sheet in three and then in half: the packet of about 4¼ × 3⅔ in fits, but it is bulky and the extra crease shows. An A4 sheet folded in three is too wide and slightly too tall as well, which is why letters in the UK and Europe go in a DL envelope.

Printing the address at home

A Monarch envelope is narrow enough for most home printers, which usually take envelopes short edge first through a manual or rear slot. Which way the flap should face differs by model, so check the envelope symbol on the tray. Before you use the good stationery, print a test on plain paper cut to size and hold it against an envelope to see where the address lands.

The button on this page opens the label editor at the Monarch size, laid out the way the guide to addressing an envelope describes. A serif font such as EB Garamond or Cormorant Garamond usually suits executive letterhead better than a plain sans serif. If your printer won't feed envelopes reliably, print the addresses on labels instead; the guide to printing envelopes at home explains both routes.

Postage in the US and the UK

In the US, a Monarch envelope travels as an ordinary First-Class Mail letter. Up to 11½ × 6⅛ in, ¼ in thick, 3.5 oz is what USPS counts as a letter, and a Monarch is well inside those measurements, so only an envelope stuffed past them would pay the higher large-envelope price. A Forever stamp pays for the first ounce, and two or three sheets of letterhead normally weigh less than that, so one stamp is usually enough for a flat, undecorated envelope. Heavy cotton paper or an enclosure can push a letter into the next ounce, and the stamp calculator shows what a heavier letter needs.

Personal stationery sometimes has a wax seal or ribbon, which makes the letter rigid or lumpy, and that changes the price because USPS charges the non-machinable surcharge for envelopes that are rigid or lumpy or have clasps, string or buttons, and asks you not to put rigid objects such as coins, keys or flash drives in a letter. For specially decorated envelopes, USPS lets you pay the non-machinable surcharge and ask the Post Office counter to hand-cancel them, and for wax seals, strings, ribbons and other decorations on the outside it advises not to send them exposed but to put the envelope inside another envelope, and a Monarch fits easily inside a #10 envelope for that. Neither route reliably avoids the extra charge, though: a thick seal can still make the outer envelope lumpy or rigid, and hand-canceling at the Post Office counter means paying the non-machinable fee as well. So for a Monarch with a seal or ribbon, plan on paying the non-machinable surcharge on top of the Forever stamp.

In the UK, the same envelope counts as a standard Letter. Up to 24 × 16.5 cm, 5 mm thick, 100 g is what Royal Mail accepts as a Letter in both 1st and 2nd Class, and a Monarch envelope with a few sheets inside is comfortably within those limits. An ordinary 1st or 2nd Class stamp therefore does the job, and only an envelope beyond those limits would become a Large Letter, which needs a Large Letter stamp.