Agencies do not have projects so much as accounts that keep going, and that is what most portals get wrong about them. The retained relationship has no delivery date that ends it, several people on the client side who each care about different things, a stream of approvals that hold everything up when they stall, and a body of finished work that somebody will want to find in two years. A client portal for agencies is judged on how it handles that continuity, not on how well it presents a single project.
Approvals are the bottleneck, so make them impossible to miss
Almost every delay on a retained account is somebody on the client side not having approved something. The portal should show, without any navigation, what is currently waiting on the client, who specifically it is waiting on, and what it delays. Threaded feedback in an email chain is where approvals go to become ambiguous, and ambiguity here is billable time nobody bills for.
Several people, several interests, one account
The marketing manager wants the work, the finance contact wants the invoices, the director wants the summary. One shared login serves none of them well and cannot be cleaned up when somebody leaves. Individual access with sensible defaults per person is not a luxury on an agency account, it is the difference between a portal being used and being forwarded around as screenshots.
The archive is the part that survives you
Agency staff turn over, and so do client contacts. Two years in, the person asking where the brand guidelines are was not present when they were written. A portal that keeps every deliverable filed against the account, with a date and a version, means the answer is a link rather than an archaeology exercise through somebody's former mailbox.
Questions people ask about client portal for agencies
Should an agency portal show hours or budget burn?
It depends entirely on your commercial model. If you bill for time, transparency here usually prevents arguments rather than causing them. If you bill fixed fees, showing hours invites a conversation about the wrong thing.
Is a shared drive enough for agency clients?
It handles deliverables and nothing else. Approvals, status and who is waiting on whom are exactly what it cannot represent, and those are what cost agencies money.
Should the portal carry our branding or the client's?
Yours. The client is buying your service, and a portal in a software vendor's name makes an agency look like a reseller of somebody else's process.