Invoice Cancellation Pro for WHMCS

Invoice Cancellation Pro lets your clients cancel their own unpaid invoices directly from the client area. Clients simply click Cancel Invoice, choose a reason, and confirm. No ticket, no staff intervention.

You decide exactly what qualifies. By default, only unpaid invoices with no payment and no credit applied are eligible. You can narrow eligibility further by invoice age, value, product, payment gateway, or client group. Anything outside your rules simply won't show the cancellation button.

Cancellation is performed through the official WHMCS interface, so your existing hooks, logging, and client notifications continue to behave normally. Every rule is also enforced again server-side before anything is cancelled, so a visible button is never treated as permission on its own.

Beyond the cancellation button, the addon captures why clients cancel and maintains a complete audit trail including the reason, client's own words, amount, invoice, and IP address. A built-in dashboard helps you understand the most common cancellation reasons over time.

Client Experience

• Self-Service Cancellation — A Cancel Invoice button appears on every eligible unpaid invoice, allowing routine cancellations without contacting your support team.
• Confirmation Before Anything Happens — The invoice is clearly identified, the action is marked as permanent, and a Keep Invoice option closes the confirmation window without making any changes.
• Reason Capture — Clients choose from your configured reasons and can add a note in their own words. Individual reasons can require an explanation before the cancellation can be submitted.
• Never a Silent Failure — Every refusal returns a specific, translatable message explaining why the action cannot proceed.
• Hidden When It Wouldn't Work — Ineligible invoices do not display the cancellation button, so clients are never offered an action that would fail.
• Mobile Ready & Translatable — Fully responsive on mobile devices, with every client-facing string editable through the standard WHMCS language override system.

Eligibility & Control

• Safe By Default — Out of the box, only unpaid invoices with no payment recorded and no credit applied can be cancelled.
• Age Limits — Add a cooling-off period before cancellation is offered, or a cut-off after which older invoices must be handled manually.
• Value Thresholds — Keep larger invoices under staff control while allowing smaller invoices to be cancelled automatically.
• Product, Gateway & Group Exclusions — Protect products involving setup work or contracts, exclude particular payment methods, and keep reseller or wholesale accounts out of the self-service flow.
• Per-Client Rate Limiting — Limit how many invoices an individual client can cancel within a rolling window.
• Master On/Off Switch — Disable the entire feature instantly. Nothing is rendered and the cancellation endpoint refuses requests while disabled.
• Choose Where They Land — After cancellation, send clients back to the invoice, their invoice list, or the client area homepage.

Appearance

• Works On Any Theme, No Template Edits — The cancellation button works with default, custom, and third-party client area themes, including themes that do not render the standard hook tags.
• Ten Button Styles — Classic, Solid, Soft, Dark, Tailwind, Ghost, Pill, Minimal, Gradient, and Theme Default.
• Five Confirmation Window Styles — Light, Dark, Tailwind, Minimal, and Glass.
• Live Previews — Preview each style directly in the admin panel using the real client stylesheet.
• Or Use Your Own — Theme Default removes the module's styling so your existing button classes take over.
• Custom Label & Placement — Change the button wording and optionally position it using a target selector when the automatic placement is not suitable.
• Adapts To Your Front End — Detects Bootstrap 5, Bootstrap 3/4, or no framework and adapts to the environment without fighting your theme's existing styles.

Reasons

• Seven Ready To Use — Sensible default reasons are configured on activation, so the addon is useful immediately.
• Fully Editable — Rewrite wording, reorder the list, add custom reasons, or deactivate reasons that don't fit your business.
• Require An Explanation — Configure individual reasons to require a written note, ensuring responses such as Other can still provide useful information.
• History Is Never Rewritten — The reason wording shown at the time of cancellation is stored with each log entry, so editing or deleting a reason later does not change historical records.
• Optional Requirement — Make selecting a reason mandatory or allow clients to cancel without selecting one.

Reporting & Audit

• Find Out Why People Cancel — See your most common cancellation reasons ranked over time.
• Dashboard At A Glance — View totals for today, this week, and this month, cancelled value by currency, and a 30-day trend chart.
• Complete Activity Log — Record the client, invoice, amount, currency, reason, client note, source, status, and IP address for every cancellation attempt.
• Combining Filters — Filter by date range, client email, invoice ID, reason, or status to investigate specific periods or activity.
• CSV Export — Export exactly what your current filters show, ready for accounting or further analysis.
• Reason On The Invoice — Optionally write the cancellation reason and client note into the invoice's own notes field so staff can see them directly in WHMCS.
• Email Notifications — Optionally receive a notification when a client cancels, including the invoice, amount, reason, and client note.
• Retention You Control — Delete individual entries, clear entries matching your current filters, or configure automatic pruning to match your retention policy.

Security & Reliability

• Nothing Bypassed — Cancellation is performed through the official WHMCS interface, allowing existing hooks, logging, and client notifications to behave normally.
• Every Rule Re-Checked Server-Side — The complete eligibility check runs again when the request is submitted. A visible button is never treated as permission on its own.
• Ownership Enforced — Every request is validated against the account that owns the invoice, preventing clients from acting on another client's invoice.
• No Double Cancellations — Each invoice is locked while the request is processed, preventing double-clicks, multiple tabs, or simultaneous sessions from producing duplicate cancellations or records.
• Request Verification & Throttling — Every submission carries a verified session token and repeated attempts are rate-limited.
• Safe Exports — Client-supplied text is escaped during CSV export so notes cannot execute as spreadsheet formulas.
• Settings Validated On Save — Configuration values are validated and constrained server-side independently of the form controls.
• Services Left Untouched — Cancelling an invoice is a billing action only. No service is suspended or terminated automatically.

Admin Panel

• Dedicated Admin Interface — A clean sidebar panel covering Dashboard, Activity Log, Reasons, Settings, and License.
• Live In Minutes — Upload, activate, and enter your license key. Production-ready defaults mean no configuration is required before enabling the feature.
• Self-Healing Install — The module checks and repairs its own setup whenever the admin page loads, helping recover from incomplete uploads.
• Deep Links Throughout — Log entries link directly to the related invoice and client record for quick investigation.
• Your Data Stays Yours — Deactivating the module preserves settings, reasons, and log entries so nothing is lost when the feature is temporarily disabled.

Compatibility

• WHMCS: 8+
• PHP: 8.1+
• ionCube Loader: v15
• Database: MySQL 5.7+ or MariaDB 10.3+
• Client Area Themes: Works with any client area theme — no template changes required
• License: Valid license required