Plain-English USPS guides for postage, addressing, Certified Mail, tracking, and delivery timing.
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Use this guide before mailing when you need the right apartment, unit, suite, or floor abbreviation and placement. Includes USPS-friendly examples for secondary address formatting.
Does UPS deliver to PO boxes? Learn when UPS Ground Saver or USPS Street Addressing works, plus alternatives for receiving your packages.
Learn where to find your Certified Mail tracking number, check delivery status, and get proof of delivery when available.
Check whether USPS is delivering today, including Sundays, federal holidays, and local service alerts. Use this 2026 guide for same-day mail status.
Yes, USPS delivers letters and packages on Saturday. See guarantees, Post Office hours, collection times, and common exceptions.
Compare USPS First-Class Mail vs. Priority Mail for letters and documents, including cost, delivery time, tracking, and Certified Mail options.
Use the USPS stamp calculator to figure out how many Forever or additional-ounce stamps to use by weight and envelope type. Need dollar postage rates instead? See 2026 USPS postage prices.
Check USPS postage for letters, postcards, and large envelopes, with weight-based prices and a link to the postage calculator.
Learn how to address a letter to a judge, format the envelope and salutation, avoid ex parte contact, and use a sample character-reference letter.
Put the recipient name first, the PO Box number on the next line, and the city, state, and correct PO Box ZIP Code on the final line.
Learn where to write the address, message, and stamp on a postcard, plus the size and postage basics before you mail it.
Put your return address in the upper-left corner, the recipient address in the center, and postage in the upper-right corner. Here is the straightforward USPS-friendly format.
Use the correct APO, FPO, or DPO military address format. Learn where the name, unit, AA/AE/AP code, ZIP Code, postage, and customs form belong.
Use indelible black ink, conceal the check, mail it before the last pickup, and choose tracking or proof of delivery when the payment matters.
Use our DMV checker for all 50 states and DC to find online options and mail-in guidance for registration renewals, replacement titles, and license renewals.
Learn how to mail sensitive documents safely, choose USPS tracking or proof of delivery, protect private information, and keep useful mailing records.
Learn how to write a certified letter with the correct format, sample wording, a complete example, and a reusable template for important notices.
USPS First-Class Mail has an estimated delivery window of 1 to 5 business days. Learn what affects the service standard and compare USPS mail classes.
Square invitation? Stiff greeting card? Find out when you need extra postage and whether your envelope can be mailed as a letter.
Check your passport application status through the State Department and use USPS tracking when your finished passport book is mailed back to you.
Compare 2026 USPS PO Box rates by size, published UPS Store mailbox prices, and virtual mailbox plans. Find exact local prices and sources.
Registered Mail starts at $20.90 plus postage. Fees depend on declared value and include applicable insurance up to $50,000. Learn how its security and delivery work.
Keep the mail unopened, mark it Refused or Not at this address as appropriate, and return it to USPS. Learn when new postage is required.
A self-addressed stamped envelope is an envelope someone can use to mail something back to you. Here is how to prepare it without mixing up the two addresses.
Learn how USPS General Delivery works, who can use it, how to find a participating Post Office, and the address format and ID needed to pick up your mail.
USPS Hold Mail pauses delivery for 3 to 30 days at your local Post Office. Learn how scheduling, identity verification, pickup, and redelivery work.
Check USPS holidays in 2026 and whether regular mail service is scheduled today. Calendar-based results, plus links to local Post Office hours and service alerts.
Use c/o when another person or business receives mail on someone’s behalf. Use ATTN when mail has reached the correct organization but needs to be routed internally.
Check USPS international tracking options, find your destination country’s tracking page, understand missing updates, and see when to open a USPS inquiry.
If a letter or package never arrived, start with tracking and then use the USPS Missing Mail process when the mailpiece is eligible for a search.
Set up USPS mail forwarding, choose a temporary or permanent Change of Address, learn what gets forwarded, and manage or extend your request.
What a quiet USPS tracking page can mean, how to read the current status, and when to use USPS support or Missing Mail.
Use our IRS mailing address finder to find where to send tax returns, amended returns, extensions, and payments by state, form, and delivery method.
Learn why you might receive Certified Mail, what to do after delivery, how to spot scams, and what happens if you do not pick it up.