Corporate tax

In Quebec, businesses and companies must annually fill out a T2 federal tax return form. In addition, they must also fill out a form for their provincial tax return called the "CO-17 tax return." Both forms are required. However, errors are common, so how do you avoid them? 

Here are some tips to help you properly fill your CO-17 tax return:

CO-17 Tax return: have the right help when filling this form

Knowing how to fill out the CO-17 tax return form is not evident for everyone. Indeed, the CO-17 tax return addresses many things you need to know in order to prevent making mistakes when filling it out.

This is why businesses and companies often go to accountants. Through their experience and professionalism, you can be assured that they will avoid any mistakes. Furthermore, for some time it has been possible to fill out your tax returns electronically thereby facilitating the work of some "amateurs".

Indicate the correct tax year end date on your CO-17 tax return form

During the first year of your company or business, you will be required to fill out the CO-17 tax return. In doing so, you must indicate the date of incorporation of the company or the business as a reference point. So, the following year, you must file your tax return form within one day of this end date. If you want to change the end date for your company, you must make a request to the tax services office in your area by specifying the reasons for your change.

Enter the correct address of your business or your company

This may seem obvious, however it is one of the most common errors in tax returns. Often, the reason is related to a non-advised move. Failing to notify the Canada Revenue Agency (CRA) could interrupt your tax refund.

Do not throw anything away

Keep all your old tax returns, receipts and bills that can be audited after examining your CO-17 return. Keep all documents for up to 6 months after filing. These documents serve as evidence and may be useful to you for certain returns such as moving expenses, for example.

Avoid being late with your CO-17 tax return form

Filing your tax return past your end date may result in penalties such as an imposition of 5% on the amount and an additional 1% for each month late incurred over a maximum of 12 months. There are also penalties of $25 per day late, up to $2,500. Often businesses and companies make this mistake, thinking they are not taxable, so be careful! So make sure to file your taxes on time to avoid any late fees!

Nowadays, it is possible to declare income electronically, which reduces some mistakes especially when filing your T2 and CO-17 tax returns.

To maximize the chances of avoiding errors, your business or company needs to be vigilant when filing your CO-17 tax return. This involves turning to the right person to fill it out, being very careful when filling it out, having the proper documents to submit and above all filling everything out on time. This obviously does not exclude tax returns filed online or people with no income. 

For more information on the CO-17 tax return, please visit Quebec Revenue website or contact our professionals to accompany and assist you as needed.

Frédéric Roy-Gobeil


As President of T2inc.ca and an entrepreneur at heart, I have founded many start-ups such as delve Labs and T2inc.ca. A former tax specialist at Ernst & Young, I am also a member of the Ordre des comptables professionnels agréés CPA and have a master's degree in taxation from the Université de Sherbrooke. With a passion for the world of entrepreneurship and the growth mindset, I have authored numerous articles and videos on the industry and the business world, as well as on accounting, taxation, financial statements and financial independence.

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