GLS US package tracking, and the API behind it.
GLS's West Coast parcel network, formerly Golden State Overnight. One free lookup a day, no sign-up.
Also known as GSO, Golden State Overnight, GLS USA.
GLS US tracking numbers
We recognize these formats from the number alone. For anything else from GLS US, add ?carrier=glsus.
- GLS number or shipper reference
- 9 digits; pass ?carrier=glsus (not auto-detected)
- Example (format only)
- 512345678
- Category
- Regional and last mile
- API carrier code
- glsus
GLS US tracking API quickstart
One request per number, or up to 100 at once with ?numbers=a,b,c. Your agents can use the same data over MCP.
REST
curl "https://api.lastscanned.com/v1/track/512345678?carrier=glsus"Claude Code
claude mcp add --transport http lastscanned https://mcp.lastscanned.comThen ask
> Where is my GLS US package 512345678? When will it arrive?
GLS US tracking FAQ
- How do I track a GLS US package?
- Paste the tracking number into the lookup on this page. We read GLS US's own tracking data and show every scan, the current status and the delivery details. Anyone can do one lookup a day without signing up.
- Is there a GLS US tracking API?
- Yes. GET https://api.lastscanned.com/v1/track/:number?carrier=glsus returns GLS US tracking as JSON, in the same shape as every other carrier lastscanned covers. Sign up for a free key with 5 lookups a day, or Pro for $4.99 a month with 1,000 numbers.
- What does a GLS US tracking number look like?
- GLS number or shipper reference: 9 digits; pass ?carrier=glsus (not auto-detected). For example 512345678. lastscanned recognizes these formats on its own, so ?carrier=glsus is optional for them.
- Does this work for GSO and Golden State Overnight and GLS USA numbers?
- Yes. They are tracked through GLS US and come back as carrier "glsus".
- Can an AI agent track GLS US packages?
- Yes. Add lastscanned as an MCP server (https://mcp.lastscanned.com) in Claude, ChatGPT, Cursor or VS Code and ask it where a GLS US parcel is.
Other carriers
Major carriers
Regional and last mile
Tracking pages are for people. This is for your code.
Every carrier shows a parcel differently. lastscanned reads them all and answers in one shape, so your app, your spreadsheet or your agent handles any carrier the same way.
| Carrier website | lastscanned API | |
|---|---|---|
| Carriers | One carrier per site | 31 carriers behind one endpoint |
| Response | A web page to read | The same JSON for every carrier |
| Volume | One number at a time | Up to 100 numbers per request |
| Agents | Copy and paste | MCP server for Claude, ChatGPT and Cursor |
| Automation | Check back by hand | Poll from your own code or workflow |
Free: 5 numbers a day with a key. Pro: $4.99 a month for 1,000 numbers, then $0.015 each.