Knowledge Centre

PEO publishes a variety of resources to assist licence holders in their roles and responsibilities, as well as guidance for applicants going through the licensure process.


Ontario professional engineers are part of a community of more than 87,500 PEO licence and certificate holders committed to enhancing the quality of life, safety and well-being in the province.

As Ontario’s engineering regulator, PEO relies heavily on its volunteers. More than 1,000 professional engineers, engineering interns and non-engineers volunteer their time each year on behalf of the association through their participation.

PEO's mandate, as described in the Professional Engineers Act, is to ensure that the public is protected and that individuals and companies providing engineering services uphold a strict code of professional ethics and conduct.

Online Learning Modules

PEO’s Online Learning Modules provide licence holders, volunteers, staff and applicants with various learning and development opportunities.

Practice Advice Resources and Guidelines

PEO offers a variety of practice advice resources to assist licence holders in providing professional and ethical engineering services.

Frequently Asked Questions

As with medicine and law, you require a licence to do certain engineering work within the province of Ontario. However, not everyone working in engineering requires a licence. Whether you require a licence depends on the type of engineering work you are doing, and the level of responsibility you have. The ability to practise engineering in Ontario is regulated by the Ontario Professional Engineers Act and its regulations, which outline who requires a licence, how to obtain a licence, and when a licence may be revoked. The Act is administered by Professional Engineers Ontario (PEO), a self-governing organization that grants licences to qualified individuals, disciplines licence holders who are found guilty of incompetence or misconduct, and enforces compliance with the licensing requirements of the Act. You require a licence if:

  • Your work requires you to design, compose, evaluate, advise, report, direct or supervise; and
  • The work will safeguard life, health, property or the public welfare; and
  • The work requires the application of engineering principles.

You are not required to be licensed if, for example:

  • Your work is strictly related to research, testing, or inspection; or
  • There is no risk to life, health, property or the public welfare if your work is performed incorrectly; or
  • The work is strictly scientific in nature.

There are also other exceptions to licensure in the Act:

  • You do not need to be licensed to do professional engineering if a licensed Ontario professional engineer takes responsibility for your work.
  • You do not need a licence to design tools and dies.

Any question regarding the need for a licence in a particular situation should be directed to PEO at [email protected].

No. Legally speaking, you are an engineering graduate, not an engineer. Only holders of a P.Eng. license are legally permitted to use the title “P.Eng.” or the term “engineer” in their job title, or to use any other term, title or description that may lead to the belief that they are authorized to practice professional engineering. An engineering education is the first step to earning your license and eventually having the right to call yourself an engineer, but you may only use the term “engineer” in your job title once you have P.Eng. licence.

The practice of professional engineering is defined in section 1 of the Professional Engineers Act and comprises three tests. Professional engineering is:

  1. any act of designing, composing, evaluating, advising, reporting, directing or supervising, or the managing of any of these acts
  2. wherein the safeguarding of life, health, property, economic interests, the public welfare or the environment is concerned, and
  3. that requires the application of engineering principles.

If what you do meets all three tests, you are practising professional engineering and must be licensed by the association.

The definition applies to all situations where this particular combination of intellectual activity, societal protection and methodology exists regardless of whether the position is in industry, government or consulting.

If you are going to be responsible for work that is defined as professional engineering according to the Professional Engineers Act, a P.Eng. licence may be required by law.

Becoming licensed gives you the right to use “P.Eng.” after your name and “engineer” in your job title. Under the Professional Engineers Act, you may only use “engineer” in your job title if you hold a P.Eng. licence.

The P.Eng. licence also demonstrates that you have met a rigorous educational standard, have through a demanding, hands-on internship process, and are obliged to adhere to a strict code of ethics that puts the public interest first. All of these are valued within the engineering working community and society at large, awarding you credibility and recognition.

Licensing also puts you within the professional membership community of the other 75,000 licensed professional engineers organized across the province in 36 PEO chapters.

There is no legal requirement stipulating how long documents must be retained. The documents belong to the person who created them and that person is at liberty to do with them as s/he sees fit. The most pressing reason for keeping documents is the possibility of future legal action. At present there is essentially no period of limitation so it is possible that someone can bring legal action against an engineer many years after a project is completed. Since document retention is really a matter of legal protection, you should discuss the matter with your insurance provider.

The Professional Engineers Act makes no distinction between providing professional engineering services for a fee or on a volunteer basis. The individual or volunteer organization providing professional engineering services will need a Certificate of Authorization. You should also remember that providing services as a volunteer does not make one immune to liability. Since either the client or a third party affected by the work can bring a lawsuit against the engineer or the volunteer organization, volunteers are urged to investigate their need for professional liability insurance.

This depends on whether you plan to work as an independent contractor or as a contract employee. Both arrangements have benefits for you and your employer but there are significant differences in taxation, compensation and professional responsibility. You should discuss with your former employer which arrangement to use prior to coming to an agreement on how you will provide services. PEO has published guidelines on both. Since an independent contractor is a sole proprietorship you will require a Certificate of Authorization if you decide to make this arrangement. PEO reminds professional engineers registered as retired and are paying reduced fees that they are not entitled to practice professional engineering either for payment or as a volunteer.

The Certificate of Authorization will be suspended for a period of 90 days at which time if no suitable P.Eng. has been found by the firm to replace you, the Certificate will be revoked.

Notify PEO in writing immediately about your change of employment status.

PEO has an active enforcement policy that investigates and prosecutes all reported violations of the Professional Engineers Act. If your competition is providing engineering services to the public but does not have a Certificate of Authorization then that entity is in violation of the Act. Notify PEO's Enforcement department if you encounter this situation.