Dolibarr, as an open-source ERP and CRM platform, is well-loved for its modularity and cost-effectiveness. While many commercial ERP systems lock automation features behind expensive subscriptions or paid modules, Dolibarr offers several powerful tools out of the box that, when configured properly, can automate essential business workflows. One such critical workflow is customer follow-ups, particularly for unpaid invoices or overdue payments. Automating these reminders not only improves cash flow but also reduces manual effort and ensures timely communications with clients.

This article will walk you through how to fully automate customer reminders in Dolibarr without spending a cent on paid modules. We'll explore the core tools available within the base Dolibarr installation—namely email templates, scheduled tasks (cron jobs), and built-in invoice tracking—to configure a system that sends out reminders automatically.

1. Why Automating Customer Reminders Is Important

Before diving into how, it's worth understanding why this process should be automated in the first place:

• Reduces Administrative Work: No need to track each due date manually.

• Improves Cash Flow: Timely reminders encourage faster payments.

• Professional Communication: Automated messages are consistent and standardized.

• Customer Satisfaction: Clients appreciate timely, courteous reminders instead of last-minute pressure.

Let’s now explore how Dolibarr supports this automation natively.

2. Dolibarr Invoice and Payment Overview

Dolibarr manages customer invoices through its integrated billing system. When an invoice is created, it includes due dates and payment terms. Each invoice passes through a series of statuses: draft, validated, paid, overdue, etc.

Key fields used in automation:

• Invoice Status (e.g., Not Paid, Paid, Overdue)

• Due Date

• Date of Creation

• Payment Terms

Dolibarr’s internal database tracks all these, which allows the system to flag overdue invoices.

3. Enable Scheduled Tasks (Cron) in Dolibarr

To automate reminders, Dolibarr uses scheduled tasks. These are scripts executed periodically by the system. First, ensure cron tasks are enabled:

Step-by-step:

1. Go to Home > Setup > Modules > Tools > Scheduled Jobs

2. Enable the “Scheduled Jobs” module.

3. You'll now see a list of predefined cron tasks.

Next, you need to configure your web server or hosting to trigger Dolibarr’s cron script. This is usually done using the cron utility in Unix-like systems.

Example crontab entry:

0 * * * * wget -q -O /dev/null http://yourdolibarrurl/scripts/cron/cron_run_jobs.php?securitykey=YOURKEY

Replace yourdolibarrurl and YOURKEY with the actual values.

You can find the security key in: Home > Setup > Other Setup > CRONKEY

Once configured, Dolibarr will check every hour (or whatever schedule you define) to process tasks.

4. Configuring Email Templates for Reminders

Dolibarr allows for reusable email templates that can be associated with various events, including invoice reminders.

Steps:

1. Go to Home > Setup > Emails > Email Templates

2. Create a new template (e.g., “1st Reminder – Friendly”)

3. Use dynamic tags like:

• __REF__ – Invoice reference

• __THIRDPARTY_NAME__ – Customer name

• __AMOUNT__ – Total amount due

• __DUEDATE__ – Due date

Example template:

Subject: Friendly Reminder - Invoice __REF__ is overdue

Dear __THIRDPARTY_NAME__,

This is a friendly reminder that invoice __REF__ amounting to __AMOUNT__ was due on __DUEDATE__.
Please arrange payment at your earliest convenience.

Thank you,
Your Company Name

Repeat the process to create templates for:

• First reminder

• Second reminder (more assertive)

• Final notice (legal tone)

5. Assigning Email Templates to Automatic Workflows

Now that templates are created, you need a way to automatically send them when conditions are met (e.g., overdue by X days). Dolibarr doesn’t have a built-in GUI for complex conditions, but it does support automation via the “Customer invoice reminder” scheduled job.

Steps:

1. Return to Scheduled Jobs

2. Find Customer invoice reminder

3. Click “Enable” and “Edit” the job

Set parameters like:

• Delay before first reminder: e.g., 3 days after due date

• Delay between reminders: e.g., 7 days

• Max number of reminders: 3

• Use email templates: Select the ones you created

Note: This job checks all invoices and sends reminders accordingly.

6. Ensure Email Configuration Works

For emails to be sent automatically, Dolibarr must be correctly configured with an outgoing email server (SMTP).

Steps:

1. Go to Home > Setup > Emails

2. Choose SMTP and enter your email server credentials

3. Test by sending a test email

Dolibarr logs emails, so you can verify sent messages via Tools > Emailing > Sent messages

7. Optional: Customize the Message Based on Payment Behavior

For further personalization, use custom tags or conditional phrases.

Example advanced logic:

Dear __THIRDPARTY_NAME__,

As we haven't received payment for invoice __REF__ (
__DUEDATE__), this is your second notice.

You can modify the template manually between reminders for clients known to delay payments.

8. Using Triggers and Hooks (Advanced)

For users comfortable with PHP and Dolibarr’s architecture, automation can be extended using triggers.

Create a custom trigger class in /htdocs/core/triggers/ that hooks into invoice update events and sends an email if overdue.

Example trigger: trigger_send_reminder.php

This allows custom criteria, such as sending reminders only on weekdays, only to certain customers, or after excluding public holidays.

9. Monitoring and Logs

You can track automation success via logs.

Go to Tools > Logs > Scheduled Job Logs

• View when each job ran

• Which emails were sent

• Errors or skipped jobs

Keep these monitored to ensure nothing breaks after Dolibarr updates.

10. Summary: Building an End-to-End Reminder System

By combining Dolibarr’s:

• Scheduled Jobs

• Invoice Status Logic

• Email Templates

• SMTP Configuration

You can automate customer reminders without third-party or paid modules.

Checklist:

Bonus Tip: Consider adding a small line in your invoice PDF about the reminder policy. For example:

“Unpaid invoices may trigger automated email reminders every 7 days after due date.”

Final Thoughts

While Dolibarr’s interface may not have the flashiness of big-budget competitors, its core capabilities are powerful and flexible. With a thoughtful configuration, you can build a fully automated client reminder system that helps maintain professionalism, improves cash flow, and reduces manual workloads.

The best part? You don’t need to spend a cent beyond your existing Dolibarr installation. That’s the real power of open-source ERP done right.