How to Send First Class Mail International (USPS Guide 2025)
Quick Answer: First Class Mail International
- Cost: $1.70 for 1 oz letters/postcards, $3.15+ for large envelopes
- Delivery Time: 7-21 business days (varies by destination)
- Weight Limit: 3.5 oz for letters, 15.994 oz for large envelopes, 4 lbs for small packages
- Customs Form: Required for items with commercial value; not needed for documents/letters
First Class Mail International is the most affordable way to send letters, postcards, and lightweight documents abroad through USPS. Whether you are mailing a personal letter to family overseas, sending business correspondence internationally, or shipping small documents, this guide covers everything you need to know about USPS First-Class Mail International rates, weight limits, delivery times, and customs requirements.
In This Guide
What is First Class Mail International?
First Class Mail International (FCMI) is USPS's economy international mail service for letters, postcards, large envelopes (flats), and small packages. It offers:
- Affordable rates starting at $1.70 for a 1 oz letter or postcard
- Delivery to 190+ countries worldwide
- Simple process for standard letters and documents
- No pickup required – drop in any blue collection box or post office
First Class Mail International is ideal for personal correspondence, business letters, invoices, contracts, and other documents where speed is less critical than cost.
First Class Mail International Rates (2025)
USPS First-Class Mail International rates vary by mail type, weight, and destination. Here are the current starting rates:
| Mail Type | Starting Price (1 oz) | Max Weight |
|---|---|---|
| Letters | $1.70 | 3.5 oz |
| Postcards | $1.70 | N/A |
| Large Envelopes (Flats) | $3.15 | 15.994 oz |
| Small Packages | Varies by destination | 4 lbs |
Above 1 oz, First-Class Mail International rates increase based on weight and destination country price group. Use the USPS price calculator or current Notice 123 for exact pricing to your destination.
Rate Note
The price for a 1 oz letter or postcard ($1.70) is the same for all countries. Above 1 oz, USPS uses destination price groups, so rates vary by country and weight. Rates typically increase in January and July each year.
Weight and Size Limits
Letters
- Maximum weight: 3.5 oz
- Maximum dimensions: 11.5" x 6.125" x 0.25"
- Minimum dimensions: 5" x 3.5"
- Must be rectangular
Large Envelopes (Flats)
- Maximum weight: 15.994 oz (just under 1 lb)
- Maximum dimensions: 15" x 12" x 0.75"
- Minimum dimensions: 11.5" x 6.125" (or exceeds letter thickness)
Small Packages
- Maximum weight: 4 lbs
- Maximum dimensions: Combined length + girth cannot exceed 36"
- Requires customs form
Delivery Times by Region
First Class Mail International delivery times vary significantly based on destination. USPS does not guarantee delivery dates for FCMI. These are typical timeframes:
| Region | Typical Delivery Time |
|---|---|
| Canada | 7-10 business days |
| Mexico | 7-14 business days |
| Western Europe (UK, Germany, France) | 10-14 business days |
| Eastern Europe | 14-21 business days |
| Asia (Japan, South Korea) | 10-14 business days |
| China, Southeast Asia | 14-21 business days |
| Australia, New Zealand | 10-14 business days |
| South America | 14-21 business days |
| Africa, Middle East | 14-28 business days |
Important
These times are estimates, not guarantees. Customs processing in the destination country can add significant delays. For time-sensitive international mail, consider Priority Mail International or Priority Mail Express International.
Customs Forms Requirements
When You Do NOT Need a Customs Form
- Personal letters and correspondence
- Business letters with no commercial value
- Documents (contracts, invoices, legal papers)
- Standard postcards
When You NEED a Customs Form
- Any item with commercial or monetary value
- Gifts, merchandise, or goods
- Small packages (always required)
- Items other than paper documents
Which Form to Use
- PS Form 2976: For most FCMI merchandise (typically up to about $400 in value)
- Which customs form do I need? – Complete guide to choosing the right form
Higher-Value Items
For merchandise valued over $400, First-Class Mail International often cannot be used. Higher-value items typically must be sent using Priority Mail International or Priority Mail Express International, which use more detailed customs forms (such as PS Form 2976-A). Exact requirements vary by service and destination.
How to Send First Class Mail International: Step-by-Step
Step 1: Prepare Your Mail
- Use a standard #10 envelope for letters or an appropriately sized envelope for flats
- Write the recipient address in the local format (see addressing tips below)
- Include the destination country name in English on the last line
- Write your return address in the upper left corner
Step 2: Address Format for International Mail
JANE DOE
123 CALLE PRINCIPAL APT 4
28001 MADRID
SPAIN
Always write the country name in capital letters on the last line. Use the local address format for the street address.
Step 3: Add Postage
- Weigh your letter to determine the correct postage
- Use Global Forever stamps ($1.70 each) for standard 1 oz letters or postcards
- Add additional postage for heavier items
- Or visit the post office for exact weighing and postage
Step 4: Complete Customs Form (If Required)
- Fill out PS Form 2976 if sending anything other than documents
- Describe contents accurately
- Declare the value truthfully
- Sign and date the form
Step 5: Mail Your Letter
- Blue collection boxes: Letters without customs forms can be dropped in any USPS blue box
- Post office: Required for items with customs forms
- Scheduled pickup: Available through USPS.com
Tracking Options
Standard First Class Mail International does not include tracking. Your options for adding tracking:
| Service | Cost | Notes |
|---|---|---|
| Registered Mail | Around low $20s (check current rates) | Limited tracking events, maximum security, slow |
| Priority Mail International | Around $30.90+ for Flat Rate envelopes; ~$40+ by weight | Full tracking included, faster delivery |
For detailed tracking information, see our guide: How USPS International Tracking Works.
First Class vs Priority Mail International
| Feature | First Class International | Priority Mail International |
|---|---|---|
| Starting Price | $1.70 | ~$30.90+ (Flat Rate envelope) |
| Delivery Time | 7-21 business days | 6-10 business days |
| Weight Limit | 4 lbs (packages) | 70 lbs |
| Tracking | Not included | Included |
| Insurance | Not included | Up to $200 included |
| Best For | Letters, documents, low-value items | Packages, valuable items, time-sensitive mail |
For more details, see our complete guide: How to Send Priority Mail International.
Send International Mail Online
Skip the post office. Upload your letter and we handle printing, postage, customs forms, and mailing to 190+ countries, with tracking options available.
Send International Mail OnlineFAQs
How much does First Class Mail International cost?
First Class Mail International starts at $1.70 for a 1 oz letter or postcard to any country. Large envelopes (flats) start at $3.15. Heavier letters and flats cost more based on weight and destination price group—check the USPS calculator for current rates.
How long does First Class Mail International take to deliver?
First Class Mail International typically takes 7-21 business days for delivery, depending on the destination country. Canada and Mexico are usually faster (7-10 days), while remote locations may take longer.
Do I need a customs form for First Class Mail International?
Letters containing only documents or correspondence generally do not require a customs form. For items with commercial value, use PS Form 2976 for most FCMI merchandise (typically up to about $400). Higher-value items often must be sent using Priority Mail International or Priority Mail Express International with more detailed customs forms.
What is the weight limit for First Class Mail International?
First Class Mail International letters are limited to 3.5 oz. Large envelopes (flats) can weigh up to 15.994 oz (just under 1 lb). Small packages can weigh up to 4 lbs.
Can I track First Class Mail International?
Standard First Class Mail International does not include tracking. To add tracking, you must use Registered Mail (add-on) or upgrade to Priority Mail International which includes tracking.
What happens if my letter gets lost?
First Class Mail International does not include insurance. If your mail is lost, USPS cannot provide compensation. For valuable documents, consider Registered Mail (provides security but not insurance) or Priority Mail International (includes $200 insurance).
Can I send cash in First Class Mail International?
Sending cash is generally prohibited or strongly discouraged. Many countries have restrictions on mailing currency. Use money orders or bank transfers instead.
Related Guides
- How to Send Priority Mail International
- How USPS International Tracking Works
- USPS International Delivery Times Explained
- What You Cannot Mail Internationally
- Which USPS Customs Form Do You Need?
- How to Send a Letter Internationally
Tags: first class mail international, USPS international mail, international letter rates, send mail overseas, international postage, FCMI, global forever stamp