Mandatory Alcohol Interlock Program

Strict penalties apply to NSW drivers convicted of serious and repeat drink driving offences. These offenders are restricted to driving vehicles with alcohol interlock devices for a period of time when they return to driving.

Since 1 February 2015, courts can order offenders convicted of high range, repeat and other serious drink driving offences to complete:

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

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

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.

Who is required to participate in the Mandatory Alcohol Interlock Program?

All drivers convicted of a repeat or serious drink driving offence committed on or after 1 February 2015 will receive an interlock order that requires them to participate in the Mandatory Alcohol Interlock Program (unless the court determines an exemption applies). 

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.


More information about the Mandatory Alcohol Interlock Program is available in the following guides and factsheets:

The Participant Guide includes the following forms that require completion before applying for an interlock licence:

These forms will be sent to participants as part of the requirement of an interlock order.

Interlock installation and servicing

Participants in the interlock program are required to have an interlock device installed by an accredited interlock service provider. Participants are also required to ensure their device is regularly serviced by an accredited interlock service provider during their time on the program.

The three accredited interlock service providers in NSW are:

For more information about the devices, service locations and costs offered by each interlock provider, visit their websites at the links provided.

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 $2,200 a year.

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

*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
  • Health Care Card – Low income only
  • Department of Veterans Affairs Gold Card endorsed as:
    • TPI (totally and permanently incapacitated)
    • EDA (extreme disablement adjustment)
    • War widow or war widower.

Severe financial hardship

Short-term financial assistance may be available from Roads and Maritime for participants in severe financial hardship due to unexpected circumstances. This assistance can range from partial assistance to the full amount owing to an interlock service provider. Assistance will be 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 contacted on 1300 371288.

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, which contains at each stage:

  • Three green information sheets for GPs
  • Three blue information sheets for their Practice Managers or Receptionists.

The information pack also includes an information sheet for patients, which GP provide at Stage 1 of the program.

Information sheets: General Practitioners

Information sheets: Practice Managers and Receptionists

For more information about medical consultation, please see the Fact Sheet for Medical Practitioners.

Voluntary Alcohol Interlock Program

The previous Voluntary Alcohol Interlock Program will continue for offences committed before 1 February 2015. Current participants in the voluntary interlock program will be subject to the existing conditions of the voluntary program.

If you are currently in the voluntary interlock program and wish to find the nearest service centre in your area, please contact your interlock provider directly.

Guardian Interlock Systems and Draeger Safety Pacific are the two accredited interlock service providers for the voluntary interlock program.

For more information on transitioning to the new interlock program, see the Transition Fact Sheet.

If you need a copy of the Participants guide or the Criminal Law Specialists Guide for the voluntary program, please contact us on 13 22 13.


Transport for NSW has engaged ARTD Consultants to independently evaluate the NSW Mandatory Alcohol Interlock Program, to help improve the program and to understand its road safety effects. ARTD Consultants will be interviewing and surveying participants, providers and partner agencies, and analysing road safety data.

The first survey of participants will commence in June 2016 and aims to understand participants’ experiences of the program. If you are an Interlock Licence holder (or have a court order to participate) during this time this is your chance to have your say. Survey invitations will be sent out by Accredited Service Providers and Installers. All responses will be confidential.

The first survey of installers will also commence in June 2016. Service Providers will email installers with the survey details. Responses will be confidential.

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