When it comes to mailing letters and documents that don’t require delivery confirmation, USPS First-Class Mail is a fast, affordable option. Whether you're sending invoices, appointment reminders, legal notices, or HR communications, First-Class Mail is a widely used, reliable service.
Thanks to Certified Mail Labels, you can send First-Class Mail online while skipping the trip to the Post Office. Plus, your mailing includes a free Affidavit of Mailing, helping protect you during audits or disputes.
What Is First-Class Mail?
Timely, Trusted, and Affordable
First-Class Mail is a service from the United States Postal Service (USPS) designed for postcards, letters, and lightweight documents. It delivers in approximately 2–5 business days, depending on the destination. It’s ideal for both personal and business correspondence that doesn't require tracking or signature.
Common Uses for First-Class Mail
Businesses and professionals use First-Class Mail for:
- Invoices and billing statements
- Legal letters that do not require delivery confirmation
- Notifications and reminders
- Medical records and lab results
- Lease agreements and community notices
It’s the preferred option when compliance and cost-effectiveness matter, but tracking isn't required.
What Qualifies as First-Class Mail?
USPS First-Class Mail is designed for lightweight, time-sensitive documents and correspondence. It’s a popular choice for both personal and business mail because of its affordability, reliable delivery, and ability to accommodate a wide range of items.
Eligible Items for First-Class Mail Include:
- Letters: Maximum weight 3.5 ounces (typically 1–5 sheets of paper in a standard #10 envelope)
- Large Envelopes (Flats): Up to 13 ounces
- Postcards
- Small documents or forms
All mail pieces must meet USPS size and weight standards and cannot contain hazardous materials or items prohibited in standard envelopes.
When to Choose First-Class Mail
First-Class Mail is ideal when:
- You're sending a single sheet or small packet of documents
- You need faster delivery than Marketing Mail, but don’t require tracking or signature
- The contents are time-sensitive, such as invoices, renewals, or personal correspondence
If delivery proof is required, pairing First-Class Mail letters with an Affidavit of Mailing or choosing Certified Mail with tracking is recommended.
How First-Class Mail Compares to Other USPS Services
First-Class Mail vs. Certified Mail
While First-Class Mail is fast and affordable, Certified Mail adds extra protections—like tracking numbers, mailing receipts, and Return Receipts. Certified Mail is ideal when proof of delivery or Return Signature is needed for legal or regulatory reasons.
However, many compliance documents only require proof of mailing, which First-Class Mail offers when paired with an Affidavit of Mailing.
First-Class Mail vs. Priority and Express Mail
- Priority Mail offers faster delivery (1–3 business days) and includes tracking. It’s better suited for slightly heavier or time-sensitive mailings.
- Express Mail is USPS's fastest option, offering overnight delivery at a premium price.
For everyday mailings—especially when cost savings are important—First-Class Mail is the best value.
Save Time and Money with Certified Mail Labels
Skip the Trip to the Post Office
One of the biggest benefits of using Certified Mail Labels is the ability to send mail from anywhere. No lines, no forms, no last-minute dashes to the Post Office. Just log in, print the label, and drop it in any USPS mailbox—or let us print and mail it for you.
Transparent, Pay-As-You-Mail Pricing
There are no monthly fees, contracts, or commitments. Just pay for the postage and services you use. This makes it ideal for occasional users and high-volume mailers alike.
Whether you’re mailing one document or hundreds, the platform offers a reliable and cost-effective solution.
NEW: Free Affidavit of Mailing Included
What Is an Affidavit of Mailing?
An Affidavit of Mailing is a legal document that confirms you mailed a letter to a specific recipient on a specific date. It includes the sender’s and recipient’s information, a timestamp, and details about the type of mail used.
When selected, Certified Mail Labels generates a digital Affidavit of Mailing for each First-Class letter you send, free of charge.
This can be critical for compliance, especially when mail must be sent by a certain deadline. It helps protect you from liability by proving you fulfilled your mailing obligation.
Built-In Audit Protection
In industries like law, healthcare, and property management, mailing compliance is non-negotiable. Having a time-stamped affidavit on file gives you powerful documentation to support your actions during audits or legal proceedings.
All affidavits are stored securely in your account’s 10-year data archive, accessible 24/7-365.
Certified Mail Labels Supports All Compliance Mail
Whether you’re mailing First-Class, Certified, Priority, or Express Mail, Certified Mail Labels is built for compliance-driven industries. The platform offers:
- USPS tracking and delivery confirmation (with Certified Mail)
- Return Receipt options for proof of delivery
- Affidavits of Mailing
- Same-business-day print and mail services for uploaded PDFs
- SFTP automations for recurring or high-volume jobs
- 10-year archive for all mailings
It’s no surprise that hundreds of thousands of professionals trust Certified Mail Labels with their most important mail.
Who Benefits from Online First-Class Mail?
Certified Mail Labels serves a wide range of users, including:
- Law firms mailing legal notices or contracts
- Property managers sending lease renewals or rent notices
- HR departments handling employee correspondence
- Healthcare providers mailing statements or referrals
- Financial institutions delivering compliance mail
- Government agencies communicating with constituents
If you need to mail documents efficiently while meeting documentation requirements, First-Class Mail with affidavit protection is the answer.
How to Send First-Class Mail Online
Using Certified Mail Labels is fast and easy:
- Register for a free account
- Log in and enter your return and recipient addresses
- Choose your mail options
- Print the label and affix it to your envelope—or let us print, pack, and mail it for you
- Your Affidavit of Mailing is automatically generated and stored in your account
First-Class Mail, Made Smarter
With the USPS, First-Class Mail is already a great option. But when you combine it with Certified Mail Labels, you gain unmatched convenience, legal protection, and documentation—without added cost or complexity.
Whether you're sending one letter or 1,000, Certified Mail Labels gives you everything you need to save time, reduce costs, and stay compliant.
Register for a Free Account Today!
Schedule a Live Demo to learn how First-Class Mail with affidavits can support your business needs.