WhatsApp reminders for tomorrow's appointments
Clients get a WhatsApp reminder the day before their appointment — fewer no-shows.
How it works
Trigger: Schedule — every day at 10:00
- Get tomorrow's appointments from Google Calendar.
- Find each client's phone number in the event description.
- Send each client an approved WhatsApp reminder with the time.
Diagram
Trigger App Code
Code
JavaScript used in the Code step — already included in the template below.
// Finds the client's phone number in each of tomorrow's events.
// Put it in the event description like: Phone: +201001234567
const out = [];
for (const { json: e } of $input.all()) {
if (!e.id) continue;
const match = String(e.description || "").match(/phone[^+\d]*(\+?\d[\d\s-]{7,})/i);
if (!match) continue;
const start = e.start?.dateTime ? new Date(e.start.dateTime) : null;
out.push({
json: {
phone: match[1].replace(/[^0-9]/g, ""),
client: (e.summary || "").split(" - ")[0],
time: start ? start.toLocaleTimeString("en-GB", { hour: "2-digit", minute: "2-digit" }) : "",
},
});
}
return out;Build it
Pick your tool — same automation, step by step.
Copy and paste straight into an n8n canvas (Ctrl+V), or download and use Import from File. Then connect your own credentials and replace every YOUR_… placeholder.
Show code (155 lines)
{
"name": "WhatsApp reminders for tomorrow's appointments (Flowngn)",
"nodes": [
{
"parameters": {
"content": "## WhatsApp reminders for tomorrow's appointments\nClients get a WhatsApp reminder the day before their appointment — fewer no-shows.\n\n**Setup**\n1. Open each node and connect your own credentials.\n2. Replace every YOUR_… placeholder.\n3. Test once, then activate.\n\nFree template from Flowngn",
"height": 260,
"width": 340
},
"id": "292c1d67-c80f-4cc7-af9e-c21711972859",
"name": "Setup notes",
"type": "n8n-nodes-base.stickyNote",
"typeVersion": 1,
"position": [
-420,
-60
]
},
{
"parameters": {
"rule": {
"interval": [
{
"triggerAtHour": 10
}
]
}
},
"id": "292c1d67-c80f-4cc7-af9e-c21711972859",
"name": "Every day 10:00",
"type": "n8n-nodes-base.scheduleTrigger",
"typeVersion": 1.2,
"position": [
0,
0
]
},
{
"parameters": {
"operation": "getAll",
"calendar": {
"__rl": true,
"value": "primary",
"mode": "id"
},
"returnAll": true,
"timeMin": "={{ $today.plus({ days: 1 }).toISO() }}",
"timeMax": "={{ $today.plus({ days: 2 }).toISO() }}",
"options": {
"singleEvents": true,
"orderBy": "startTime"
}
},
"id": "292c1d67-c80f-4cc7-af9e-c21711972859",
"name": "Tomorrow's appointments",
"type": "n8n-nodes-base.googleCalendar",
"typeVersion": 1.3,
"position": [
300,
0
]
},
{
"parameters": {
"jsCode": "// Finds the client's phone number in each of tomorrow's events.\n// Put it in the event description like: Phone: +201001234567\nconst out = [];\n\nfor (const { json: e } of $input.all()) {\n if (!e.id) continue;\n const match = String(e.description || \"\").match(/phone[^+\\d]*(\\+?\\d[\\d\\s-]{7,})/i);\n if (!match) continue;\n\n const start = e.start?.dateTime ? new Date(e.start.dateTime) : null;\n out.push({\n json: {\n phone: match[1].replace(/[^0-9]/g, \"\"),\n client: (e.summary || \"\").split(\" - \")[0],\n time: start ? start.toLocaleTimeString(\"en-GB\", { hour: \"2-digit\", minute: \"2-digit\" }) : \"\",\n },\n });\n}\n\nreturn out;"
},
"id": "292c1d67-c80f-4cc7-af9e-c21711972859",
"name": "Find client phones",
"type": "n8n-nodes-base.code",
"typeVersion": 2,
"position": [
600,
0
]
},
{
"parameters": {
"operation": "sendTemplate",
"phoneNumberId": "YOUR_PHONE_NUMBER_ID",
"recipientPhoneNumber": "={{ $json.phone }}",
"template": "YOUR_REMINDER_TEMPLATE|ar",
"components": {
"component": [
{
"type": "body",
"bodyParameters": {
"parameter": [
{
"type": "text",
"text": "={{ $json.client }}"
},
{
"type": "text",
"text": "={{ $json.time }}"
}
]
}
}
]
}
},
"id": "292c1d67-c80f-4cc7-af9e-c21711972859",
"name": "Send reminder",
"type": "n8n-nodes-base.whatsApp",
"typeVersion": 1,
"position": [
900,
0
]
}
],
"connections": {
"Every day 10:00": {
"main": [
[
{
"node": "Tomorrow's appointments",
"type": "main",
"index": 0
}
]
]
},
"Tomorrow's appointments": {
"main": [
[
{
"node": "Find client phones",
"type": "main",
"index": 0
}
]
]
},
"Find client phones": {
"main": [
[
{
"node": "Send reminder",
"type": "main",
"index": 0
}
]
]
}
},
"pinData": {},
"settings": {
"executionOrder": "v1"
},
"meta": {
"templateCredsSetupCompleted": false
},
"tags": []
}In Make, create a new scenario and add these modules in order:
- Schedule the scenario: Every day 10:00
- Google Calendar › Search Events
- Tools › Set variable / Iterator + Array aggregator (same logic as the Code step)
- WhatsApp Business Cloud › Send a Template Message
- Every module run uses Make operations — the free plan includes a monthly quota.
- Make's built-in functions (map, sum, formatDate…) can replace most Code steps; for complex logic use a code module.
- Module and step names can differ slightly as Make and Zapier update their apps.
In Zapier, create a new Zap and add these steps in order:
- Schedule by Zapier — Every day 10:00
- Google Calendar — Find Events
- Code by Zapier — Run JavaScript (paste the code from the Code section)
- WhatsApp — Send Template Message
- Zaps with more than two steps need a paid Zapier plan.
- Webhooks, Filters/Paths and Code by Zapier are premium features on some Zapier plans.
- Code by Zapier runs JavaScript: reuse the code shown above, reading inputs from inputData instead of $json.
- Module and step names can differ slightly as Make and Zapier update their apps.
Tips
- Write the client's number in the event description like: Phone: +201001234567
- Add Confirm / Reschedule buttons to the template to cut no-shows even more.
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