Alcohol Interlock Program

Drivers convicted of serious drink driving offences are restricted to driving vehicles with alcohol interlock devices for a period of time when they return to driving. This ensures offenders separate their drinking from driving and do not re-offend. The program is designed to reduce drink-driving and improve safety for all road users.

What is an interlock?

Interlocks are electronic breath testing devices linked to the ignition system of cars, motorcycles and heavy vehicles.

Drivers must provide a breath sample that the interlock analyses for the presence of alcohol before the vehicle will start.

If a positive sample is detected, the vehicle will not start. Randomly timed breath tests must also be passed during a journey. The interlock also includes a camera and takes a photograph of the person providing the breath sample to reduce the risk of a driver circumventing the program.

Who is required to participate in the Alcohol Interlock Program?

All drivers convicted of high-range, repeat and other serious drink-driving offences in NSW committed on or after 1 February 2015 are required to have an interlock installed.

The program also now applies to drivers convicted of middle-range drink-driving, and driving a motor vehicle under the influence of alcohol offences committed on or after Monday 3 December 2018.

Since 28 June 2021, drivers convicted of a combined drink and drug driving offence are also required to have an interlock installed.

Offenders are ordered by the court to complete:

  • A minimum licence disqualification period, and
  • A period of participation in the interlock program (at least 12 months).

The length of the minimum disqualification and interlock period depend on the offence type. Longer periods apply for the most serious offences.

The Court may grant an exemption from participating in the interlock program, but only in limited circumstances.

Interlock offences, disqualifications and interlock periods

* This table outlines the disqualification and interlock periods in section 211 which apply to offences committed on or after 3 December 2018. Offences of this type that occurred between 1 Feb 2015 and 2 Dec 2018 are subject to the law in place at the time of the offence.

What happens if I do not install an interlock?

A person who receives an interlock order and does not enter the interlock program will be disqualified from holding a licence (other than a learner or interlock licence) for a period of five years from the date of their conviction. Heavy penalties apply for driving while disqualified.

What should I do to get started?

Transport for NSW will send you a letter when your minimum licence disqualification period is almost complete and you are eligible to get your interlock licence.

The Participant Guide outlines the key steps to get your interlock licence and important information about the program. You can also start with the Getting started – Quick Guide or watch a short video.

If you have questions, or have not received a letter from Transport for NSW, call us on 13 22 13.

Interlock installation and servicing

Participants in the interlock program are required to have an interlock device installed by an accredited interlock service provider. The device must be installed before an interlock licence can be issued. When your device is installed, the provider will explain how to use it.

Participants are also required to ensure their device is regularly serviced by an accredited interlock service provider during their time on the program. These visits may be scheduled every 60 days, or every 90 days if you live in an area remote from a provider.

The current accredited interlock service providers in NSW are:

Visit the interlock provider websites for more information about the devices, service locations and costs offered by each provider.

Program costs

Costs associated with installing and servicing alcohol interlocks must be paid by the participant. It is estimated that the standard costs to participants will include:

  • Interlock device installation
  • Monthly device leasing
  • Regular device servicing (monthly or bi monthly) and
  • Device removal at the end of the mandatory interlock period.

These standard costs are estimated* to be about $2200 a year.

If you attempt to drink drive, or to interfere with the interlock your device, this is recorded. Your device may require extra servicing or checks at additional cost to you. 

For more information about costs please visit the interlock device provider websites at the links provided above or talk to your provider.

*Note: these are estimates only, to provide an indication of program costs. They are subject to change.

Concession rates

Interlock service providers offer a concession rate of 35 per cent off the full cost of installing, leasing, scheduled servicing and device removal if you hold a:

  • Pensioner Concession Card – full rate pension recipients only
  • Low Income Health Care Card - the letters LI must be printed on the card
  • Department of Veterans Affairs Gold Card endorsed as:
    • Totally and Permanently Incapacitated (TPI)
    • Extreme Disablement Adjustment (EDA)
    • War widow or war widower.

To receive the concession rate, you need to provide your concession card and details to your provider.

Severe financial hardship

Financial assistance is available from Transport for NSW for participants in financial hardship. This assistance can range from partial assistance to the full amount owing to an interlock service provider. Assistance is available only upon application by participants. For more information, see the Participant Guide or call us on 13 22 13. The accredited severe financial hardship assessment agency is The Salvation Army who can be reached by calling 02 8878 0151 or visiting The Salvation Army website.

Information for medical practitioners

General Practitioners (GPs) have a critical role to play in the alcohol interlock program.

There are up to three stages at which participants in the interlock program may need to visit their GP:

  • Stage 1: All participants must visit their GP before they enter the program
  • Stage 2: Some participants may be asked to see their GP at certain stages of the program because of ongoing attempts to drive after drinking alcohol indicating ongoing risky behaviour or alcohol dependence
  • Stage 3: Some participants may also be required to see their GP before completing the program, to have their fitness to drive a vehicle assessed.

To help GPs understand and fulfil this important role; an information pack has been developed across the three stages of the program:

Stage 1:

Stage 2:

Stage 3:

Information sheets: Practice Managers and Receptionists

Practice Managers and receptionists also have a critical role in supporting general practitioners and participants at each stage of the program. The following fact sheet has been developed to support practice managers and receptionists:

Stage 1:

Stage 2:

Stage 3:


Video - Alcohol interlock program overview

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