PEO signs off before your first invoice
Holding a P.Eng licence lets you practise engineering; it does not let a business offer engineering services to the public. Any entity that does so in Ontario, whether a sole proprietorship, partnership or corporation, needs a Certificate of Authorization from PEO, with one or more licensed engineers designated as assuming responsibility for the professional work. Two practical points catch new firms:
- The name is regulated. The Professional Engineers Act restricts business names suggesting an entitlement to practise engineering, so clear the proposed name against both the corporate registry and PEO's rules before printing anything.
- Insurance is a disclosure obligation. A C of A holder either carries professional liability insurance or tells each client in writing that it does not. Most clients worth having will not accept the second option, so the insurance conversation belongs in the setup budget, not after the first RFP.
- It is not one-and-done. The C of A renews annually, and the designated engineers must stay current, so a departure or retirement in a small firm can put the certificate itself at risk if nobody is watching succession.
Our Incorporation service runs the sequence as one project: articles and share classes drafted with the C of A application in view, so nothing is filed twice.
An ordinary corporation, and why that is good news
Ontario reserves its professional-corporation regime for professions like medicine, law and accounting; engineers are not on the list. An engineering practice therefore incorporates as a standard Ontario business corporation that then obtains its C of A, and the differences all cut in your favour. A spouse can hold shares directly. A family trust or holding company can sit in the structure. Retained profits can move to a holdco by tax-free intercorporate dividend, out of reach of operating risk. None of that is available to a physician's MPC without contortions, and none of it requires PEO's blessing on the shareholder list.
The honest caveat: flexibility of ownership is not flexibility of income. Dividends to family members still face TOSI, and paying them well requires the groundwork covered in our Tax Planning & Advisory work, not just a share certificate.
Does the corporation actually pay?
For a firm with staff and retained profits, usually yes. For a solo consultant, it depends on two numbers and one risk. The numbers: profits left in the corporation are taxed at roughly 12.2% on the first $500,000 versus personal rates that reach 53.53% at the top Ontario bracket, but the deferral only exists on money you do not need to live on. The risk: a one-client consultant may be a personal services business, which erases the rate advantage entirely; that assessment should precede incorporation, and it is treated in depth on our engineer tax planning page.
| Sole proprietor with a C of A | Corporation with a C of A | |
|---|---|---|
| Tax on retained profit | Personal marginal rates, up to 53.53% | About 12.2% on the first $500,000 |
| Liability for design errors | Yours; insurance responds | Still yours professionally; the corporation shields commercial debts |
| Who can own it | You alone | Family, trusts and holdcos permitted; TOSI governs dividends |
| Admin load | T1 self-employment schedule | T2, minute book, payroll and HST accounts |
Note the liability row. Incorporation never shields an engineer from professional negligence on work bearing their seal; insurance does that job. What the corporation shields is the commercial layer: the lease, the equipment loan, the contract dispute that is not about the engineering.
The setup, in order
Where two or more principals incorporate together, the shareholder agreement matters as much as the articles: a buy-sell mechanism, a valuation formula that reckons with WIP and receivables rather than just book value, and a plan for what happens to shares when a designated engineer leaves. Writing that down at incorporation costs a fraction of negotiating it during a falling-out.
Done as one project from our Mississauga office, the sequence is short: name cleared against corporate and PEO rules; articles with a useful share structure, ordinary and dividend-sprinkling classes drafted with TOSI reality in mind; CRA program accounts, HST from day one since engineering fees are taxable, payroll when the first salary runs; the C of A application with its designated engineers and insurance declaration; then banking, books and a first-year calendar so instalments and filings never surprise you. Solo consultants who mostly need a fast answer channel between engagements often start with CPA Quick Support at $99 a month and step up when the firm grows into monthly accounting.
Source: Ontario — Professional Engineers Act, R.S.O. 1990, c. P.28.
