SMS Reminders

Last updated: 2026-06-22

On Pro and Team plans, any reminder step can also go out as a text message — useful for clients who live in their phone, or as the extra nudge on a final-notice step.

Turning it on

Three switches control SMS, and all three must be on:

1. Per step — in Settings → Reminder schedule, expand a step and tick "Also send as SMS". Steps with SMS on show a small phone icon when collapsed.
2. Master switch — in Settings → Notifications, enable SMS notifications for your account.
3. Client phone number — the client record needs a phone number in international format (e.g. +14155551234). You can type it however you like — spaces, parentheses and dashes are fine, and 00 works in place of + — and Duefy tidies it to the standard format for you. It just needs the country code (the +1, +44, …); a number without one is flagged so it's fixed before it can quietly fail to send. Clients without a phone simply don't get the SMS; the email still goes out as normal.

What the message says

By default Duefy builds a concise reminder that leads with your business name and includes the invoice number, the amount, the due or overdue status, and a secure pay link — for example:

Acme Co: Invoice #INV-1042 for USD 1,500.00 is 9 days past due. Pay now: https://… Reply STOP to opt out.

To keep the pay link from being cut off, a reminder may arrive as two linked SMS segments rather than being forced into a single 160-character message. Every message ends with "Reply STOP to opt out" so recipients can unsubscribe — this is also required by mobile carriers.

Customizing the text

When you switch SMS on for a step, an SMS text box appears. Leave it blank to use the smart default above, or write your own — handy for a different tone or a non-English message. As you type, a live preview shows the text filled with sample data, plus a character count and how many SMS segments it will use (more segments cost more).

• Use the same merge tags as email — {{client_first_name}}, {{invoice_number}}, {{amount}}, {{due_date}}, and so on (click Insert variable to add them).
• Your text must include {{payment_link}} so the client can pay — otherwise the schedule won't save.
• You don't need to add the opt-out; "Reply STOP to opt out" is appended automatically if it isn't already there.

Good to know

• SMS goes out alongside the email for that step, never instead of it.
• Every SMS is recorded on the invoice timeline, like emails.
• Clients can reply. A text back lands on the invoice timeline ("Client replied via SMS") and gets the same AI triage as an email reply (Pro and Team) — so a promise to pay, a dispute, or a payment claim surfaces the same way.
• Opt-outs are honored. If a client texts STOP (or UNSUBSCRIBE, CANCEL, etc.), Duefy records it and won't text that number again; texting START re-enables it. This is separate from the email unsubscribe — a client can stop texts while still getting email reminders, and vice-versa.
• Standard carrier rates apply on the recipient side; Duefy does not charge per message.
• Fair use: each plan includes a generous monthly SMS allowance, shown under Settings → Plan & Billing → Usage & credits. If you reach it, texts pause for the rest of the month while your email reminders keep going out as normal; the count resets at the start of the next month. It's never a surprise: a banner warns you as you approach the limit, and we email you once when you hit it.
• See every text: the View SMS history link on that same usage card opens an itemized log — each text sent that month, the client and invoice, the number it went to, and whether it was sent or failed. Use the month arrows to look back.
• Need more? Buy a text top-up pack from Settings → Plan & Billing → Usage & credits (bigger packs cost less per text, and extra texts draw from your credit balance), or connect your own Twilio. You can buy packs during your trial too.
• Use your own Twilio (optional): in Settings → Notifications you can connect your own Twilio account. Reminders then send from your own number with no monthly cap, and Twilio bills you directly — handy for high SMS volume.