A prison engine number is a local Australian phone number that connects calls from a correctional centre directly to your mobile. When your loved one calls the engine number from the prison phone, they pay the facility’s local-call rate — typically $0.30 to $0.40 per call — instead of mobile rates that can reach $0.90 per minute. The call rings straight through to your mobile, wherever you are.
The Original — Trusted Since 2004
Australia’s original and leading engine number and 3CX service for prisoners. Over 30 million calls connected for more than 100,000 Australian families. All plans unlimited — long-term plans from just $0.92/day, the lowest published per-day unlimited engine number rate in Australia. More connected calls than any other Australian engine number service, on enterprise-grade 3CX infrastructure built for reliability. Every number works through each facility’s own contact-approval process — nothing connects without the prison approving it first.
How a Prison Engine Number Works
- You choose a plan and we assign you a local number in the region of your loved one’s prison.
- They add the number to their approved contact list at the facility (the standard approval process every number goes through).
- They call the engine number from the prison phone — charged at the local-call rate.
- Your mobile rings. No special equipment. The 3CX app is optional — most families just answer on their normal mobile.
What Prison Calls Cost — With and Without an Engine Number
| Call type | Typical cost to the inmate |
|---|---|
| Prison phone → mobile | up to $0.90 per minute (a 10-minute call can exceed $7) |
| Prison phone → local number (engine number) | $0.30–$0.40 per call |
| Engine Numbers plan (your side) | from $0.92/day on long-term plans; short-term from $2.50/day |
For a family speaking daily, that’s the difference between roughly $200+ a month in call costs and a fixed plan from about $28 a month — savings of up to 80%.
Compliance and Safety: How Our Technology Meets the Rules
This is the question families worry about most, so here is how our service is built. Engine Numbers provides a compliant service, engineered from the ground up to meet correctional regulations — using a series of technologies developed over twenty years:
No call diversion
Our technology ensures calls cannot be diverted. The call your loved one makes connects only to its registered destination.
Locked answering location
Once your service is activated, the answering location cannot be changed. The inmate can only ever reach the approved person the number was set up for.
Active misuse monitoring
Our systems check for conference-call participation and other abuse of the service. Where misuse is detected, that service is cancelled.
The facility stays in control
Every number goes through the prison’s own contact-approval process — nothing connects without the facility approving it first.
These controls exist for one reason: they ensure the safety of everyone — inmates, families, and the facilities themselves. It’s why we’ve been trusted to connect over 30 million calls since 2004.
How to Get a Prison Engine Number
- Pick a plan — daily ($2.50), weekly ($10), monthly ($34), quarterly ($96), 6-month ($189) or yearly ($336, about $0.92/day). No lock-in contracts, cancel anytime.
- We assign your local number, usually within minutes.
- Your loved one submits the number for approval at their facility.
- Once approved, calls connect at local rates. If they transfer prisons, we help you update the number — free.
Why Families Choose Engine Numbers
The original
Operating since 2004 — longer than any other provider in Australia.
No surprises
Flat plans, no top-ups, no lock-in, cancel anytime.
Real support
Phone and email support from an Australian team: 02 9070 9777.
150+ facilities
Across NSW, VIC, QLD, SA, TAS and ACT.
Frequently Asked Questions
What’s the difference between a “prison engine number” and a “jail engine number”?
Nothing — they’re the same thing. “Jail” and “prison” are used interchangeably in Australia. See our jail engine numbers page for more.
Will the prison know it’s an engine number?
Every number is submitted through the facility’s normal contact approval process. Approval decisions rest with each facility.
Can the number receive calls from more than one inmate?
In many cases yes, provided each facility approves the number on their contact list.
What happens if my loved one is transferred?
Contact us — we’ll help update the prison location, and if a different local number is needed we’ll guide you through the change at no cost.
Do I need the 3CX app?
No. It’s optional. Most families answer on their normal mobile. If you want the app, see our 3CX engine number guide.
How fast is setup?
Most families have their engine number within minutes of signing up. The facility’s approval of the number is the only waiting step.
What Prison Calls Cost — and How an Engine Number Helps
Many families go looking for cheaper prison calls because a call from a correctional centre to a mobile can cost many times more than a local call. A local engine number brings the call back to the facility’s local-call rate — which is why it remains the most affordable way for most families to stay in touch.
The right plan depends on how often your loved one calls and how long you’ll need the number: daily and weekly plans suit short stays, while monthly and longer plans work out cheapest for regular contact — see our current plans and pricing. And for a full, neutral breakdown of what prison calls cost in every Australian state — including the documents behind Queensland’s 2025 price change — see our public resource, Prison Call Costs Australia.