How to Send Invoice Payment Reminders from Google Sheets (2026)

Once invoices live in a Google Sheet, the next problem is usually collection: which ones are unpaid, which are overdue, and who should get a polite reminder. Highlighting helps when you open the sheet. A daily script can email the client (or you) seven days before the due date, on the due date, and a week later if it is still unpaid.

To create the invoice PDF from each row, use the invoices and certificates guide. This page is only about reminders. For a generic date-column reminder (one email, any kind of date), see automatic email reminders from a date column.

Step 1: columns for unpaid work

Create a tab named Invoices with: Invoice #, Client, Email, Amount, Due date, Status, plus Sent 7d before, Sent on due, and Sent 7d after. Status values such as Draft, Sent, Paid and Overdue are enough. Format Due date as a date and Amount as currency.

In Days overdue (due date in column E, status in F):

=IF(OR(F2="Paid",F2="Draft",E2=""),"",IF(E2<TODAY(),TODAY()-E2,0))

A simple aging label:

=IF(OR(F2="Paid",F2="Draft",E2=""),"",IF(E2>=TODAY(),"Current",IF(TODAY()-E2<=30,"1-30 days",IF(TODAY()-E2<=60,"31-60 days","60+ days"))))

Step 2: highlight what is unpaid and late

Select the data from row 2 and add conditional formatting:

A filter view named “Unpaid overdue” is enough for a weekly collection pass.

What native notifications will not do

Tools › Notification settings (and conditional notifications, where available) email people when cells are edited. They do not send a reminder because a due date arrived, and TODAY() formulas do not trigger conditional notifications while the sheet is closed. See Google's conditional notifications help.

Step 3: three reminder steps, no duplicates

Open Extensions › Apps Script, paste the script, save, run sendInvoiceReminders once to approve permissions, and add a daily time-driven trigger. Draft and Paid invoices are skipped. Each step has its own sent column so a late invoice can receive the “7 days before” email (if you turned this on while it was already inside the window), the due-date email, and one overdue follow-up, each only once.

/**
 * Payment reminders for unpaid invoices: 7 days before due, on the due date,
 * and 7 days after if still unpaid.
 * Columns: A Invoice # | B Client | C Email | D Amount | E Due date | F Status
 *          G Sent 7d before | H Sent on due | I Sent 7d after
 * Skips Status Draft or Paid (any case). Trigger: daily time-driven on sendInvoiceReminders.
 */
function sendInvoiceReminders() {
  const sh = SpreadsheetApp.getActive().getSheetByName('Invoices');
  const rows = sh.getDataRange().getValues();
  const today = new Date(); today.setHours(0, 0, 0, 0);
  const tz = Session.getScriptTimeZone();
  const steps = [
    { offset: 7,  col: 7, label: 'due in 7 days' },
    { offset: 0,  col: 8, label: 'due today' },
    { offset: -7, col: 9, label: '7 days overdue' },
  ];

  for (let r = 1; r < rows.length; r++) {
    const inv = rows[r][0], client = rows[r][1], email = rows[r][2];
    const amount = rows[r][3], due = rows[r][4], status = String(rows[r][5] || '');
    if (!email || !(due instanceof Date)) continue;
    const st = status.toLowerCase();
    if (st === 'draft' || st === 'paid') continue;
    const dueDay = new Date(due); dueDay.setHours(0, 0, 0, 0);
    const left = Math.round((dueDay - today) / (24 * 60 * 60 * 1000));
    const amountText = (typeof amount === 'number')
      ? amount.toLocaleString('en-US', { style: 'currency', currency: 'USD' })
      : String(amount);
    const dueText = Utilities.formatDate(due, tz, 'MMM d, yyyy');

    for (const s of steps) {
      if (left > s.offset) continue;          // not yet at this step
      if (rows[r][s.col - 1]) continue;       // already sent
      if (MailApp.getRemainingDailyQuota() < 1) return;
      const subject = 'Invoice ' + inv + ' ' + s.label;
      const body = 'Hi ' + client + ',\n\nThis is a reminder that invoice ' + inv +
        ' for ' + amountText + ' is ' + s.label + ' (due ' + dueText + ').\n\nThank you.';
      MailApp.sendEmail(email, subject, body);
      sh.getRange(r + 1, s.col).setValue('Sent ' + Utilities.formatDate(new Date(), tz, 'yyyy-MM-dd'));
    }
  }
}

Edit the message body to match how you already write to clients, and include a payment link or invoice PDF URL if you store one in another column. Keep the tone factual: invoice number, amount, due date.

Caveats

Want reminders without maintaining a script? SheetReminders (disclosure: we make it) is a Google Sheets add-on that watches a date column and sends scheduled email reminders before, on or after each date, for example 30, 14 and 7 days before a due date, or after a date for overdue follow-ups. Sheet data stays inside your Google account and it uses narrow scopes. 14-day free trial, no credit card required. It is live on the Google Workspace Marketplace.
See SheetReminders
Short on time? Watch the 50-second version

Related Google Sheets guides

Instructions refer to Google Sheets, Google Docs, Google Forms, Google Drive and Apps Script as they worked on November 10, 2026. Not affiliated with Google or any other vendor named here. Google Sheets, Google Docs, Google Forms, Google Slides and Google Drive are trademarks of Google LLC. Features change, so verify in your own account. Questions or corrections: hello@loomwise.app.