The phone system.
Billed your way.
The Phone System addon puts Giant VoIP in your WHMCS, under your brand: your customers' whole phone-system portal, call billing at your prices, number choice and a 999 address at checkout, number ports, and 999 records. All through the Giant Reseller API.
- PHP 7.4 to 8.4
- Needs Giant Reseller 2.3.0+
- ionCube-encoded
- Your branding
- Call billing at your rates
Not sure? In WHMCS, open Utilities › System › PHP Info — or run php -v on the server.
fd31c6f5e6ad3f07879d53f5ef4dc496e8204f8734b45f46bc5ccfa2cb2626f5Needs the ionCube Loader for PHP 8.4 on your server — most hosts already have it.
Their whole phone system. Your name on it.
From checkout to the phone estate, every page is built from the API for the customer's own services only.
The whole phone-system portal
Extensions, numbers, call flows, voicemail, recordings, the app, AI agents, and the rest, on every VoIP service's page. Your branding throughout.
Pick numbers at checkout
Area codes, number types, and memorable numbers, with your margin on the setup fee. The numbers go to Giant with the order.
999 address up front
A structured emergency address on the product's configuration page, sent with the order.
Inclusive minutes, shown at checkout
A minutes panel that scales with the seats or numbers they pick.
Port a number
Every port across their services in one place, with progress emailed to them as it moves.
999 records
Every number's emergency record, with a refresh and a per-number view.
Their phone estate
Spend, forecast, and health, with drill-down, for their services only.
Spend and history
This period's spend and calls, inclusive minutes left, and billing history. Call logs show your price, never Giant's cost.
Every call priced at your rates. Every night.
- 01
Collect
Every night, each service's calls and SMS from the Reseller API.
- 02
Price
At your rates: uplift, exempt prefixes, SMS price, minimum charge, rounding.
- 03
Inclusive minutes
Prefix groups per extension, number, or service, used per second before a call is charged.
- 04
Approve
Approve, override with a reason, decline, or recompute at today's rates. Or switch on auto-approve.
- 05
Invoice
Onto an open invoice or a new one, with inclusive minutes shown on the line.
Nothing slips through. Nothing goes unbilled.
Reconcile against Giant, catch seats and numbers you aren't billing, and let the scheduled jobs chase ports and 999 records.
Charges
What was decided on every billing window, with invoice links.
Reconcile
Your collected cost beside Giant's closed periods.
Leaks
Seats and numbers you bill, against what Giant bills you and what's live.
Alerts
A day's spend far above a service's recent average, and a daily digest of windows awaiting approval. Stuck windows flagged at 35 and 90 days.
Daily port check
Progress emailed to the customer; a completed port adds its numbers to the service's billed quantity.
Weekly 999 sweep
Emergency records checked through the API every week.
Email templates, yours to edit
App login and welcome (from you, with your app name), port submitted, port update, billing digest, and high-usage alert.
Cron log
Every scheduled run, with a Run-now button.
All of it, through the API.
Estate, services, 999 records, numbers, and ports: the addon calls the same Reseller API you can call yourself. The release zip ships a parity checklist and a sandbox run sheet, so you can rehearse it on a sandbox key first.
Wholesale voice →$ Your VoIP estate — every tenant, its numbers, and billing
Four steps. Straight from the README.
- 01
Giant Reseller module first
The addon runs on the Giant Reseller WHMCS module, 2.3.0 or later. Install that first.
- 02
Match your PHP
Download the build for your WHMCS server's PHP version: Utilities › System › PHP Info, or php -v.
- 03
Upload one folder
Copy modules/addons/resellervoip into your WHMCS modules folder. The server needs the ionCube Loader.
- 04
Follow the guide
Its chapter is in the setup guide: in the zip, and in WHMCS under Addons › Giant Reseller › Setup guide.
whmcs/
└── modules/
├── servers/giantreseller/ ← 2.3.0+, first
└── addons/
├── giantreseller/
└── resellervoip/ ← this addon
├── lang/ ← edit the wording
└── templates/ ← edit the client areaEvery version. Every change.
Straight from the addon's release feed, including the history of the module it replaced. Subscribe by RSS.
v3.2.4
Latest15 October 2026- The phone-system pages (the service page, Port a number, 999 records, the estate, the services list) carry their own colour palette, so they look right on any WHMCS theme; before, their styles read colour variables only Giant's own theme defined, leaving them unstyled on a reseller's site
- New setting "Accent colour": a hex colour for buttons, tiles and highlights on those pages and at checkout; blank keeps the default blue
v3.2.3
15 October 2026- Guide tab: common problems and their fixes (ionCube Loader, missing number picker, tax wording, call charges, the module log); the full list is in the setup guide's Troubleshooting chapter
v3.2.2
15 October 2026- Checkout: three or more number tiles per row; the number-type and area-code filters are stacked full width with controls of one height; the active filter pill's label is always readable
v3.2.1
15 October 2026- Fixes the service page's script (broken in 3.2.0 by the tax-wording change) and the port form's remaining "ex. VAT"
v3.2.0
15 October 2026- Tax wording follows your WHMCS tax settings: gold-number setup fees and port prices say "+VAT" / "ex VAT" only when tax is enabled and the product is taxable, "inc. VAT" when your prices are entered inclusive of tax, and nothing at all when you do not charge tax; the tax's name comes from your first tax rule (VAT, GST, Sales tax…)
v3.1.7
15 October 2026- Checkout: the number tiles are square-cornered and sit in a grid that fits as many per row as the page width allows (no more four cramped columns); a gold number's setup fee is written inside its tile on its own line; the chosen-number chips match
v3.1.6
15 October 2026- Checkout: the per-number monthly price chip no longer prints over the number on narrow tiles (it sits after the number and only shows when the grid is wide enough); the active filter pill's label is white on the accent colour
v3.1.5
15 October 2026- Checkout: a stylesheet comment named the supplier; reworded (the leak test now guards the checkout stylesheet too)
v3.1.4
15 October 2026- Checkout: the number picker sits in its own card with its own colours on any WHMCS theme (it relied on Giant's theme variables, so dropdowns had no background and the block floated); dark themes keep dark controls
v3.1.3
15 October 2026- Checkout: numbers are searched for every area code (the ported script only searched areas tagged with a carrier, so geographic areas showed nothing), and the API's national numbers are matched to the chosen area correctly, so the tiles appear
- Checkout: no carrier names in the page's markup
v3.1.2
15 October 2026- Checkout: the number search reads the endpoint's answer whether or not the browser already parsed it, and when the search is refused or fails it says why in the number panel instead of silently showing nothing
v3.1.1
15 October 2026- Fixes the daily call collection, Reconcile and Leaks stopping on a wrong class name introduced in 3.1.0
v3.1.0
15 October 2026- Module log: every API call the addon makes, every portal action with what was posted and what was answered, the checkout's decisions, the cron runs, billing approvals and the emails it sends are written to the WHMCS module log under "resellervoip" while module logging is on; passwords, keys and tokens are blanked
- Checkout: the number picker no longer stops before drawing (it expected a pre-loaded number list); numbers load per area as before
- Needs the Giant Reseller module 2.3.1 or later
v3.0.3
15 October 2026- Checkout: when the numbers option is marked Hidden in WHMCS (so it is not on the form), the picker posts the chosen quantity itself, so the order carries the right number count
v3.0.2
15 October 2026- Checkout: when the number picker cannot be shown, a signed-in WHMCS admin sees the reason on the configuration page (customers see only "not available right now"); it is also in the page source and the activity log
- Checkout: an area name with an apostrophe no longer stops the picker's script
v3.0.1
15 October 2026- Checkout: the numbers and seats options are now found however the product names them ("Telephone Number(s)", "Phone Numbers", "Extensions/Users" and the names in the settings all work), so the number picker and the minutes panel appear on products imported from Giant
- Checkout: the "Telephone Numbers (DIDs)" box imported from Giant's product is hidden, since the picker fills the numbers in
- Checkout: when numbers cannot be offered (no numbers option, or no area codes from the API) the page says so in its source and the activity log, instead of showing nothing
- Billing and Leaks use the same option matching for the billed seats and numbers
v3.0.0
15 October 2026- First release of the Phone System addon, numbered after the Giant API UK VoIP Reseller Provisioning & Addon Module (2.0.1 on the WHMCS Marketplace) that it replaces: the whole phone-system portal, call billing at your prices, checkout with number choice and 999 address, number ports, 999 records and the phone estate, all through the Giant Reseller API with your branding
- Needs the Giant Reseller module 2.3.0 or later; one zip per PHP version (7.4 to 8.4), encoded with ionCube 15
- Guide chapter in Addons > Giant Reseller > Setup guide, and the parity checklist and sandbox run sheet in the module's tests folder
- Known limits in this release: CRM sign-in integrations, estate exports and the optimisation wizard, AI and storage metered re-billing, and extension QR login codes are not available through the API yet and are shown as such
Giant API: UK VoIP Reseller Provisioning & Addon Module
View on WHMCS Marketplacev2.0.1
7 May 2023- Automated monthly call billing, custom call bundle packages, and automatic creation of the custom fields and configurable options the module needs
- Client area: live call logs, Zerotouch hardware auto-provisioning, SMS logs and outbound SMS, and management of hunt lists, telephones, IVR menus, extensions, call queues, forwarding destinations, short numbers, number purchasing and voicemail
v1.1
20 July 2022- Zerotouch hardware provisioning
- Fewer custom fields needed to provision a service
- Virtual Landline product for resellers
v1.0
1 June 2022- First release: automatic provisioning of UK VoIP tenants from the reseller's own WHMCS installation
Straight answers. From the release notes.
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Tell us what you're building and the wholesale team will get you set up on Giant VoIP.