An estimate (shown as "Proforma" in the menu) is a proposal you send a client to accept or decline.
Statuses and who moves them
Draft → Sent (you press Send) → Viewed (the client opens the link) → Accepted or Declined (the client decides) → Converted (you turn an accepted one into an invoice). Expired happens by itself.
You cannot mark an estimate accepted or declined yourself, and nothing moves backwards. Declined, expired and converted are dead ends: to quote again, create a new estimate (there is no duplicate button).
The proposal link
A client needs no account. The link is signed for that one estimate and carries no expiry of its own; it stops working only when the estimate is expired, accepted or declined, or put in Trash. Treat it like a key. Re-sending the email reuses the same link.
On the page the client sees your logo and brand colour, the line items, tax, total, notes and terms, in the site's language. They can download the PDF.
Accepting needs their full name typed as an e-signature and a ticked "I agree to the terms" box. Declining takes an optional reason. After either, the page cannot be changed.
A draft's link is a private preview: the client cannot accept or decline it until you send it.
Optional items
Mark a line Optional and the client can untick it; every optional line starts ticked. The total is recalculated from what they keep, and that snapshot is what is recorded. The accepted total can therefore be lower than the total you sent. Once accepted, the estimate can no longer be edited.
Viewed
A sent estimate becomes viewed the first time the proposal link is opened. Opening it yourself from Copy proposal link counts too, and so can an email scanner, so treat it as strong evidence that the link was fetched, not proof the client read it. Looking at the estimate in the admin never marks it.
Expiry is lazy
Set Valid until and the estimate cannot be accepted after that day (the day itself still works). But nothing runs on a schedule: a sent estimate flips to expired only when the Estimates list loads it or the client opens the link. The detail page and counters can show "Sent" a little longer than they should. Estimates with no valid-until never expire; new ones get one from the Valid days setting.
Notes are client-visible
Notes appear on the proposal page and the PDF. Use them only for things the client may read.
Editing after sending
You can still edit a sent or viewed estimate. The same link then shows the new content, and the client is not told. Press Send again to email the new PDF. Accepted estimates are frozen.
Converting
An accepted estimate can be converted into a draft invoice. It copies the client, address, currency, tax rate and notes, plus every required line and the optional lines the client kept, with their line discounts; the estimate discount becomes the invoice discount. Title, terms and valid-until are not copied. The invoice gets its own next number (from the linked invoice series if the estimate's series has one). The estimate's status becomes converted, linked to the invoice, and it cannot be converted twice. Review and send the invoice yourself.
Who is told
When a client accepts or declines, all admins get a bell notification linking to the estimate. Nothing is sent when it is viewed, expires or converts. Automations can react to sent, accepted, declined, converted and expired, and can create and send an estimate.