WHMCS knows exactly which clients use which products and servers, which makes it ideal for targeted messages – a maintenance notice to everyone on one server, or an offer to clients of one plan. Its reports then show how the business is doing. This guide covers both.
Before you start
- Working SMTP; bulk mail through PHP Mail will land in spam. See WHMCS SMTP setup.
- Understand consent rules: service messages (maintenance, billing) can go to all clients; marketing needs opt-in in many countries.
Marketing consent
Under Configuration → System Settings → General Settings → Mail (or Other), enable Marketing Emails Opt-in so clients choose at signup and can change it in their profile. WHMCS records consent history, which helps with GDPR compliance.
Send a mass email
- Go to Utilities → Mass Mail Tool (in some versions Clients → Mass Mail Tool).
- Choose the Message Type: Client, Product/Service, Addon or Domain.
- Set filters, for example:
- Clients in a client group or country.
- Services on a specific server – perfect for maintenance notices.
- Services of certain products and statuses (Active only).
- Marketing opt-in only for promotional content.
- Click Compose Message.
- Write the subject and message; merge fields such as
{$client_first_name}and{$service_domain}work here. - Use Send Test or preview, then Send Message.
WHMCS queues messages and sends them in batches. Large lists take time; keep within your SMTP provider's sending limits.
Network issues instead of email
For outages, also post under Support → Network Issues. Affected clients see the notice in the client area, which reduces duplicate tickets.
Reports worth checking
| Report | Shows |
|---|---|
| Monthly / Annual Income | Revenue per period |
| Income by Product | Which plans earn most |
| New Customers | Signups over time |
| Client Statement / Aging Invoices | Who owes what and for how long |
| Cancellations / Churn | Lost services and reasons |
| Ticket Feedback / Support Ticket Replies | Support load and quality per staff member |
| Server Revenue Forecasts | Recurring revenue per server |
Open them under Reports. Most can be filtered by date and currency and exported to CSV for spreadsheets or accounting software.
Troubleshooting
- Mass mail stuck: the cron processes the queue; check that it runs. See cron troubleshooting.
- Many bounces: old client addresses; clean them up and close inactive accounts.
- Reports look wrong: check currency filters and that payments were recorded against invoices.