What is First Class Mail? A Guide for eCommerce Sellers
For eCommerce businesses, every dollar saved on shipping counts — and USPS First Class Mail continues to be one of the most cost-effective and reliable ways to send small, lightweight packages within the United States. Whether you’re shipping handmade goods, accessories, or beauty products, understanding how First Class Mail works can help you lower costs without sacrificing service quality.
Let’s explore what First Class Mail offers, how it compares to other services, and when it’s the right choice for your eCommerce shipping strategy in 2025.
What Is First Class Mail?
USPS First Class Mail is a low-cost service designed for mailing letters, flats, and parcels up to 13 oz. While it’s often associated with personal mail, it’s also a go-to option for small businesses shipping lower-weight items.
What Can eCommerce Sellers Send with First Class Mail?
- Jewelry, accessories, and cosmetics
- Small electronics or parts (e.g., chargers, phone cases)
- Clothing items like socks, t-shirts, or hats
- Marketing inserts or product samples
- Anything under 13 oz that fits in a small package or envelope
USPS First Class Mail: Pros and Cons for Online Sellers
Pros:
- Very affordable for lightweight shipments
- Delivery within 1–5 business days
- Tracking included for parcels (not for envelopes or flats)
- Great for subscription boxes and low-cost items
Cons:
- No default insurance coverage
- No guaranteed delivery window
- Not ideal for higher-value or urgent shipments
How Much Is First Class Postage in 2025?
Cost of a First Class Stamp
For standard mail, a 1 oz letter requires a $0.68 stamp.
Pricing for eCommerce Packages
Packages shipped via First Class start at around $4.75 for parcels under 4 oz, with rates increasing based on weight and zone. Each additional ounce for letters adds $0.24.
| Package Weight | Estimated Price |
|---|---|
| 4 oz | ~$4.75 |
| 8 oz | ~$5.55 |
| 13 oz (max) | ~$6.90 |
First Class Mail Delivery Time
How Long Does It Take?
First Class Mail typically delivers in 1 to 5 business days, depending on distance. For most metro areas, delivery is closer to 2–3 days.
USPS First Class vs Other USPS Services
| Service | Delivery Time | Starting Rate | Tracking | Insurance |
|---|---|---|---|---|
| First Class Mail | 1–5 business days | ~$4.75 | Yes* | No |
| Ground Advantage | 2–5 business days | ~$5.50 | Yes | $100 |
| Priority Mail | 1–3 business days | ~$8.70 | Yes | $100 |
*Tracking is included for parcels, but not for letters or flats unless upgraded with extra services.
Does First Class Mail Include Tracking?
- Yes, but only for packages (not for standard letters or flats).
- Tracking can be added to other mail types using Certified Mail or Registered Mail, at an additional cost.
For eCommerce sellers, USPS automatically provides a tracking number for First Class parcels — a must-have for customer satisfaction and dispute resolution.
When Should eCommerce Sellers Use First Class Mail in 2025?
Use First Class Mail when:
- Shipping products under 13 oz
- Delivery time is flexible
- Cost control is a top priority
Avoid First Class Mail when:
- Shipping high-value products needing insurance
- You need guaranteed delivery speeds
- You require tracking for every envelope or flat
Ideal Use Cases:
- Etsy or Shopify sellers shipping handmade items
- Subscription boxes with small, recurring shipments
- Product samples or promotional mailers
Summary: USPS First Class Mail is a powerful tool for eCommerce sellers in 2025 looking to reduce shipping costs for smaller packages. It offers a smart mix of affordability, reliability, and simplicity — as long as you stay within the size and weight limits. For budget-conscious businesses, it’s one of the best values in domestic shipping.