What is a TMS API?
A TMS API is a programmable interface that lets external systems — ERPs, shops, accounting, telematics, customer portals — read and write data in your transport management system. It’s how your TMS talks to the rest of your stack without humans copying data between screens.
In 2025, a TMS without a real API is a liability. Every integration becomes a custom project, every connector a maintenance burden.
What an open TMS API typically lets you do
- Read orders, shipments, trips, customers, invoices, CO₂.
- Create orders from an external system (ERP, shop, EDI).
- Update order status, stop status, ETA, POD.
- Push invoices and cost lines into accounting.
- Subscribe to events (order created, shipment delivered) via webhooks.
A modern TMS exposes this through a REST API plus OAuth2 for secure third-party access. Routix does both — see the API documentation.
Open TMS vs closed TMS
| Open TMS | Closed TMS | |
|---|---|---|
| Public API documentation | Yes, self-service | ”Contact us” |
| OAuth / third-party apps | Yes | Custom integration project |
| Webhooks | Yes | Rare |
| Sandbox environment | Yes | Maybe |
| Integration cost per connector | Hours | Weeks, billed |
| Lock-in risk | Low | High |
A “closed TMS” doesn’t mean it has no API — it usually means the API is private, undocumented, and only accessible to the vendor’s own integration team.
What to ask any TMS vendor
- Is the API documentation public? If you have to sign an NDA to see it, it’s not really open.
- Is there a sandbox? No sandbox = no real developer integration.
- OAuth2 with scopes? Otherwise third-party apps can’t be granted limited access.
- Webhooks or only polling? Polling makes real-time integration painful.
- Rate limits? They exist — make sure they fit your volumes.
- Versioning policy? What happens when the API changes?
Why this matters for transport operators
- ERP integration (sync customers, push invoices) — done once, used forever.
- Shop integration (e-commerce orders → TMS orders) — automatic order intake.
- Telematics integration (GPS → shipment status) — see track and trace.
- Customer portal (your customer reads their own orders) — fewer status calls.
- Your own tools — dashboards, reports, mobile apps you build yourself.
Routix is API-first: every screen in the app uses the same API that’s exposed to integrators. There is no “hidden” backend.
Related concepts
See this in Routix
If integration capability is the deciding factor, start on www.routix.com and then continue to the API documentation. Routix exposes the same operational model used by the app itself, which is the practical difference between an API-first TMS and a closed one.
