Stop chasing overdue invoices with emails nobody reads. Connect Xero with Monster SMS and send automated SMS reminders the moment a payment is late. Your cash flow will thank you.
Free plan available. No credit card required. 5c per message on paid plans.
Sound familiar?
Australian SMEs carry an average of 23 overdue invoices at any given time. Chasing them by phone and email burns hours every week and still gets ignored.
Accountants and bookkeepers waste time reminding clients to reconcile before BAS lodgement. A simple SMS a week before the deadline saves everyone the scramble.
Invoice reminder emails are opened less than 25 per cent of the time. SMS messages are read within 3 minutes, 98 per cent of the time. The channel you use matters enormously.
What you can automate with Monster SMS and Xero
Trigger an SMS reminder automatically when an invoice passes its due date. Set reminders at 3 days, 7 days, and 14 days overdue without lifting a finger.
Remind clients to send through missing documents, reconcile accounts, or review transactions before the quarterly BAS lodgement window closes.
Send an automatic thank-you SMS the moment a payment is marked as received in Xero. Customers feel acknowledged and disputes drop dramatically.
Customers can reply directly to your SMS to ask for a payment plan, dispute an amount, or confirm ETA. Replies land in your Monster SMS inbox instantly.
How it works
Link your Xero account to MonsterSMS.ai through Zapier. No developer needed. Most businesses are set up and sending in under 15 minutes.
Write your SMS templates once. Pull in Xero fields like customer name, invoice number, amount, and due date so every message is personalised automatically.
When an invoice hits overdue status in Xero, the reminder goes out on schedule. You get paid faster without adding a single task to your day.
Trusted by Australian businesses
"We used to spend Friday afternoons calling clients about overdue invoices. Now Monster SMS handles it automatically when something goes past due in Xero. Our average days-to-pay dropped from 38 to 14 days."
Mel D. - Bookkeeping practice, Gold Coast QLD
Frequently asked questions
Related resources
API Integration
Monster SMS is more than a messaging tool. It is a full platform with 35 API endpoints across SMS, Contacts, Lists, AI Agents, Conversations, and Templates.
curl -X POST https://app.monstersms.ai/api/sms/send \
-H "Content-Type: application/json" \
-H "x-api-key: YOUR_API_KEY" \
-d '{
"to": "+61400000000",
"content": "Hi Tom, invoice INV-0042 for $850.00 is 7 days overdue. Pay online at pay.yourbusiness.com.au or call 1300 000 000.",
"senderId": "YourBusiness",
"callbackUrl": "https://yourbusiness.com.au/sms-callback"
}'
Fire off individual invoice or payment reminders the moment an overdue trigger fires in your accounting system.
Sync clients from your accounting software into Monster SMS with custom billing fields.
Store invoice numbers, due amounts, and account codes against each contact for personalised messages.
Create once-approved invoice reminder and payment confirmation templates for consistent messaging.
Simple, transparent pricing
Top-ups available from 5.5c per message. Free plan includes 100 msgs/month, no credit card required.
Connect Xero with MonsterSMS.ai and send automated SMS reminders the moment a payment goes overdue. Free to start. 5c per message on paid plans.
Start Free TodayFree plan available. No lock-in contracts. 5c per message on paid plans.