You send an invoice by e-mail and then… nothing. The due date is coming, the money is not. And you are stuck with a question you have had no way of answering: did the e-mail even arrive, and did the client open it? Or did it land in spam, go to a mistyped address, or sit there read and simply waiting to be paid?
The difference matters. If the client has not even seen the invoice, there is no point starting a reminder sequence — check the address and send it again. If they demonstrably opened it, you are dealing with payment, not delivery. Taxorio now shows you which of the two you are in, right on the invoice.
What Taxorio now shows
Once you send an invoice to a client by e-mail from Taxorio, a small icon appears next to it — in the invoice list and in the detail view. Hover over it and it gives you the exact date and time. Four states:
| Icon | What it means |
|---|---|
| ✉️ Sent (grey) | The e-mail went out to the client, who has not opened it yet. |
| 👁 Opened (green) | The client opened the invoice. The tooltip gives the date and time of the first open. |
| 👁 Viewed online by the client (green) | The client opened the web invoice at its public link. The tooltip gives the date and time of the first view. |
| ⚠️ Not delivered (red) | The e-mail could not be delivered — invalid address, full mailbox. Fix the address and send again. |
It is deliberately only an icon, not a new invoice status. Your invoices stay cleanly "issued / paid / overdue" — the open information is a quiet extra, not another column cluttering the overview.
Nothing to set up
The feature works automatically for invoices sent with the Send by e-mail button. Nothing to switch on, no settings to hunt through. Open measurement comes from our e-mail system, which inserts a tiny invisible image — a tracking pixel — into the message. When the client's mailbox loads it, Taxorio records the open.
Important: this is a hint, not proof
Here we will be straight with you, because open tracking has physical limits and we do not want to promise certainty that no tool on the market can give:
- False "not opened": plenty of clients have automatic image loading turned off in their mail program. The pixel never loads and the open is never recorded — even if they read the invoice three times.
- False "opened": some mailboxes, typically Apple Mail with privacy protection, load images themselves in the background before anyone opens the message. "Opened" can then appear without the client ever clicking.
Both of these weaknesses concern measurement through the pixel. The "Viewed online by the client" state does not rely on images — it arises when someone actually opens the web invoice page, so it is more conclusive. It only works one way, though: the client need not open the public link at all and can still read the invoice from the attachment.
Where to find it
The icon appears in two places:
- The invoice list — next to the invoice number, so you can take in a whole run of invoices at a glance.
- The invoice detail — in the header next to the client's name; hover for the exact date and time.
And if you connect Taxorio to an AI assistant over MCP (Claude, Cursor and the rest, on the PRO plan), the delivery status is available there too — ask for the invoice detail and the answer contains an "E-mail delivery" section.
Summary
Sending invoices blind is over. For every invoice you send you now simply know whether it arrived and whether the client opened it, and you can choose your next step accordingly. No configuration, no clutter in the overview, just a quiet icon that saves you pointless reminders and awkward phone calls — with an honest note about where its limits are, so you can lean on it sensibly.
You will find it in Taxorio on every invoice you send by e-mail. Try it on the next one, and stop guessing whether "it ever got there".
Taxorio scope: Taxorio provides invoicing and income/expense records for Czech sole traders. It is not full accounting or personalised tax advice. For an unsupported or unusual case, verify the treatment with a Czech accountant or tax adviser before filing.