Portal link’s duration
When the portal link is generated—sent via an email reminder or copied from the app—its unique token has a default 25 days validity. If your customer tries to access their link more than 25 days after receiving it, they will see an error message indicating their portal link has expired.
Manage the link duration
Manually
From your Upflow Settings, in the Customer portal section, you can update the link validity:- Minimum: 1 day
- Maximum: 1000 days
- Default is 25 days

Sending a new link to a customer does not invalidate the ones you sent previously. Each portal link stays valid independently until its own expiration date is reached, so any older link a customer still has will keep working until it expires.
API
You can also manage the links duration using our API. Here’s more details on this configuration: How to Generate a Customer Portal URL via API.Invoices links
When using the “Carrying invoice link” collection tag in your email reminders…