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Daniel Automation
Daniel Automation

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How I Automated My Invoicing and Cut Billing Time by 80%

#automation

Invoicing used to eat my Sundays. Now it takes 12 minutes per month. Here's the system I built.

The Problem

Every month was the same: Friday evening, I'd realize I hadn't sent invoices. Then I'd spend 3-4 hours:

  • Hunting down project hours
  • Copy-pasting client info
  • Formatting line items
  • Attaching receipts
  • Sending reminders when clients didn't pay
  • Tracking who paid and who didn't

By Sunday night, I'd be stressed and tired. The work was done—but the billing felt like starting over.

Sound familiar?

The Solution: The "Set and Forget" Invoice System

I built an automation that handles invoicing from tracking to payment confirmation.

Before: 3-4 hours/month of manual work

After: 12 minutes/month of review and approval

The 5-Part Automation Stack

Part 1: Time Tracking (Toggl)

What I use: Toggl Track (free tier works fine)

The setup:

  • Create projects for each client
  • Use time tags (e.g., "billable", "research", "calls")
  • Run the desktop app—it tracks automatically

The magic: At month-end, I export a CSV. Every minute is already categorized.

Time saved: 45 minutes of manual time logging

Part 2: Project Database (Notion)

I keep a simple Notion database with:

  • Client name
  • Hourly rate
  • Payment terms (Net 15, Net 30, etc.)
  • Invoice number sequence
  • Contact email for billing

This becomes the "brain" that knows what to charge and where to send it.

Part 3: The Invoice Generator (Make.com)

This is where the automation happens.

Trigger: Last day of month at 9 AM

What it does:

  1. Pulls time entries from Toggl
  2. Looks up client rates in Notion
  3. Calculates totals: hours × rate
  4. Generates a PDF using Google Docs template
  5. Saves to Google Drive (organized by client)
  6. Sends me a preview via email

I review. Click approve. It sends.

Part 4: Payment Tracking (Notion + Make.com)

Once the invoice is sent:

  • Notion status updates to "Sent"
  • Due date auto-calculated (invoice date + payment terms)
  • A reminder scheduled for 3 days before due date
  • Another reminder on due date if unpaid

I can see at a glance:

  • Which invoices are outstanding
  • Which are overdue
  • Total outstanding revenue
  • Average time to payment

Part 5: Payment Confirmation (Bank → Notion)

When a payment hits my account:

  • IFTTT detects the deposit (via email notification)
  • Make.com matches it to the invoice by amount
  • Notion updates to "Paid"
  • A thank-you email auto-sends to the client
  • Monthly revenue dashboard updates

I literally don't touch it.

The Results After 3 Months

Time spent on invoicing:

  • Before: 3.5 hours/month
  • After: 12 minutes/month
  • Time saved: 3 hours 18 minutes monthly
  • Annual savings: 40 hours (an entire work week)

Payment speed:

  • Before: Average 21 days
  • After: Average 14 days (automated reminders work)

Invoices sent late:

  • Before: 40% sent after month-end
  • After: 100% sent on time (automation doesn't procrastinate)

The Real ROI

Time saved is money earned. If your hourly rate is $100:

  • Monthly time saved: 3.3 hours
  • Monthly value: $330
  • Annual value: $3,960

The automation cost me maybe 4 hours to set up. It paid for itself in the first month.

Tools & Costs

  • Toggl Track: Free (paid tiers start at $10/month)
  • Notion: Free
  • Make.com: Free (up to 1,000 operations/month)
  • Google Docs/Drive: Free
  • IFTTT: Free

Total cost: $0

Time to set up: 3-4 hours

Ongoing time: 12 minutes/month

How to Build This Yourself

Step 1: Set Up Time Tracking (15 minutes)

  1. Create a Toggl account
  2. Set up projects for each client
  3. Start tracking today—even for 5 minutes
  4. Export a test CSV to see the format

Step 2: Build Your Project Database (20 minutes)

  1. Create a Notion database called "Client Projects"
  2. Add properties: Client Name, Rate, Terms, Status
  3. Populate with your current clients
  4. Add a "Last Invoice Number" field

Step 3: Create Invoice Template (20 minutes)

  1. Build a Google Docs template with your branding
  2. Use {{placeholders}} for dynamic content
  3. Test with fake data

Step 4: Build the Make.com Scenario (60-90 minutes)

Step 5: Test and Tweak (30 minutes)

Common Mistakes

  • Not categorizing time: If everything is "general work," invoicing is still manual. Use tags.
  • Skipping the review step: Always check before sending. Automation is fast, but it's not perfect.
  • Forgetting to follow up: Set those payment reminders. Late payments kill cash flow.

Originally published on Buy Me a Coffee. I share automation systems that save freelancers and solopreneurs 10+ hours per week.

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