You do not pick a sender address on this form. Add your addresses under the organization menu → Manage → Addresses. You choose the sender address on each shipment or in a shipping rule. Posti ships from an address in Finland or Åland, and returns come back to an address in Finland.
Before you start
- A Posti business customer account with a logistics contract number, usually six digits.
- A user in OmaPosti Pro with the API Manager role, to sign in to the Posti Developer Portal. If you do not have the role, ask your organization’s main OmaPosti Pro user to open Users management → Users, click Edit on your user, and tick API Manager under Other services.
- An application account in the Developer Portal, for the Client ID and Client secret. The steps are below.
- Optional, for tracking: a Tracking API service account from Posti customer service. You can send shipments without it.
Get your Posti credentials
1
Sign in to the Developer Portal
Open developer.posti.com and sign in with your OmaPosti Pro user.
2
Add an application account user
Open Configure application accounts → Application account list and click Add new application account user. Turn Enabled on and give it a name, for example
Zippendo.3
Select both API roles
Select shippingapi and 2026-04. Without 2026-04, you can send shipments, but the service point search and label-free returns do not work.
4
Assign your logistics contract number
Add the logistics contract number you will enter in Zippendo, then click Save.
5
Copy the Client ID and Client secret
The portal shows them once. Copy both. If you lose the secret, create new credentials in the portal and update the carrier in Zippendo.
Connect Posti
1
Open All carriers
In the sidebar, click Carriers, then open the All carriers tab.
2
Find Posti
On the Posti card, click Connect.
3
Fill in the form
The Connect carrier window opens. Carrier name is already filled in with “Posti”. Enter your Client ID, Client secret and Logistics contract number. Tracking API username and Tracking API password are under Optional fields.
4
Connect the carrier
Click Connect. You see “Carrier connected”, and the carrier appears on the My carriers tab.
The Posti card on All carriers
Connect carrier for Posti - fill in Client ID, Client secret and Logistics contract number
Fields on the form
Client secret and Tracking API password hide what you type.
Connect does nothing until Carrier name, Client ID, Client secret and Logistics contract number have a value.
Test the connection
Posti has no test system, so there is no Test mode checkbox. Every shipment you send is a real Posti shipment on your logistics contract. Posti states that a shipment is not invoiced unless it is physically shipped, so a test label you never hand over costs nothing. To try the connection, send one shipment to your own address and check its label. Posti notifies the receiver, so put your own email address and phone number on a test shipment. Zippendo cannot cancel a Posti shipment, so contact Posti if you need one cancelled. See Test mode.After you connect
The carrier appears on My carriers with a Connected badge. You choose the product on each shipment or in a shipping rule, not on this form. See Carrier products and services. A product that is not on your Posti contract is refused when you send, with Posti’s reason.
Every product except Return (Palautus) needs the receiver’s phone number, for Posti’s notices. Home Parcel (Kotipaketti) and Express Parcel (Express-paketti) can carry several parcels in one shipment. The other products take one parcel per shipment.
Services and extra details
Every product has two choices under Extra details for the carrier:- Label format: PDF (the default) or ZPL for thermal printers.
- Delivery instructions: up to 120 characters printed on the label, for example a door code.
Postipaketti service points
Postal Parcel (Postipaketti) delivers to a service point. Choose the service point in the Service point section of the shipment before you send. The search needs the 2026-04 role on your application account. See Pick a service point and Service points.Returns
Return (Palautus) brings a parcel from your customer to your address. It needs no service point, and your Posti contract must include customer returns. With Label-free return (sending code), your customer writes a code on the parcel instead of printing a label. The shipment shows the code as Label-free code under Tracking information. Send it to your customer. If Posti creates the return without a code, the shipment shows a warning. Send your customer the label instead.Customs
Shipments to a country outside the EU, and to or from Åland, the Canary Islands, Ceuta or Melilla, carry customs data from the order lines: description, tariff number (HS code), quantity, value and country of origin. Posti returns the customs declaration and the commercial invoice with the label, and they appear with the shipment’s documents. Add your EORI number under Organization settings. When the receiver has an EORI number, enter it in Receiver’s EORI number on the receiver. See Customs and documents.Pickups and tracking
- Posti is not available under Pickups. Arrange collections with Posti directly. You cannot set a pickup window on a Posti shipment. See Schedule a pickup for the carriers that are.
- When Tracking API username and Tracking API password are filled in, Zippendo fetches tracking updates from Posti about once an hour. Without them no tracking events appear. Each shipment still has its tracking number and a Tracking link to posti.fi. If the tracking login is wrong, correct it on Edit carrier and click Save. See Carrier tracking webhooks.
Change or remove the connection
To change it, open Carriers → My carriers and click Edit carrier on the card. The Edit carrier page has two sections:- General: Carrier name, and Brand if your organization has brands.
- Carrier settings: Client ID, Client secret, Logistics contract number, Tracking API username and Tracking API password.
Common problems
More help: Carrier authentication failures.