The last invoice tells you more than the usual day of the month
Open the last PDF and the billing history in your customer account, if you are authorised to access it. Compare the billed period, issue date and next renewal date. Each tells you something different: the usual day the email arrives may be neither the start of the billing period nor the date the next invoice is due.
Also check whether the service is still active and whether the plan or payment method has changed. A monthly payment does not, on its own, confirm that invoices are issued monthly. If the billing history does not explain when the next document should arrive, check the supplier's information or ask them.
In this hypothetical example, a payment for the service leaves your account every month and you expect a new email in September. But the last invoice you found covers July to September. Before asking for a September copy, you need to find out what the further payments cover and when the next document should be issued. Neither the payment nor the absence of an email answers that question.
Make sure you are looking at the right customer account
You may have a personal account and a business account with the same supplier, or several business accounts. Check the customer named on the last invoice and the service or customer identifier. Use those details to confirm that you are signed into the right account. An empty billing history in a different account tells you nothing about the invoice you need.
Then check the billing contact and delivery method. Is it your address, a shared business mailbox or the contact details of the colleague who set up the service? If someone else manages the account, ask them to check these details and any relevant message. You do not need their password or access to their personal email.
Also check whether the supplier sends the PDF itself or just a notification that a document is ready in the portal. The delivery method may have changed; compare the settings with the latest actual messages. If you find the invoice in the portal, download it manually and note where you obtained it.
Search your mailbox using details from the last message
If invoices should still arrive by email, take the exact sender address, usual subject and any customer number from the last message. Search first by sender, then by the service name or that number. The second search also helps if the supplier has changed their address. Check the archive and spam; only check other mailboxes where you have permission.
In Gmail, Google's help describes operators you can use in this example search: in:anywhere from:fakturace@example.com. Replace the address with the sender of your last invoice. The in:anywhere operator includes spam and the bin. If you find nothing, try the service name instead of the address. Do not restrict the search with filename:pdf yet: you could miss a message that contains only a portal link.
Open the specific message in any conversation you find and check its date, recipient and attachment or link. Not every message in the displayed thread necessarily matches your search. These operators work in Gmail; in other email services, use their own search tools.
Ask the supplier whether the invoice should already have been issued
If neither the account nor your email explains the gap, write to the supplier. Include the last known invoice, its billing period, your customer account and the period you are checking. The supplier can then confirm whether they have issued a new document or explain when you should expect it.
Adapt the template to what you have actually checked. If you do not know the period, ask how often the supplier invoices and which periods the invoices cover. Identify your account using a customer number or account email; do not include your password or full payment card details.
Select the text, copy it into an email and fill in the details in square brackets.
Tell your accountant what you are still checking
If you are sending documents to your accountant in the meantime, send what you have found and explain the unresolved item separately. Name the supplier, the period and who will establish and pass on the outcome. Do not resend an older invoice without explanation as a substitute for a new one.
An example message to your accountant could read: “I am checking the hosting document for September. The last invoice I found covers July to September, so I have not yet confirmed whether another document was due. I have written to the supplier and will pass their reply on to you myself. I am sending the other documents I have found now.” Your accountant then knows what you are working on and what they will still receive from you.
When the supplier replies, send your accountant the outcome. For any invoice supplied, check the customer and period and compare it with documents already handed over, so that you do not send the same file twice. If the reply does not explain whether and when an invoice is due, ask the supplier to clarify.
Keep the confirmed details for next time
For the service, note the correct customer account, confirmed billing frequency, document delivery address and where you can obtain the documents. If an incorrect contact setting caused the problem, arrange a correction with the person who manages the account. When the next invoice arrives, check that it has reached the right address.
Next time a message is missing, you will have something to compare it with: you know when to expect the document and how it should arrive. You can then go straight to checking email, opening the portal or asking the supplier about the next bill.