Canada: The TaxLetter: Amendments

Last Updated: July 22 2015
Article by Samantha Prasad

Most of you will have already filed your tax return and received your Notice of Assessment— and are now sitting back for another year of not worrying about your taxes. But there are some of you that may be rethinking your return and realize that it was not entirely correct. And then there's another group of you that may have received that dreaded Notice of Reassessment, meaning that your 2014 tax year is not yet over. If you fall into one of the latter two groups, the following discussion may shed some light on how to proceed.

Need to amend your return?

The Canada Revenue Agency's preference is that you do not file an amended income tax return in these circumstances. Instead, you should write to the Tax Centre where you filed your return, with an explanation and any additional material such as T4 slips, T5 slips and receipts requesting a change. The Canada Revenue Agency also prefers that you include form T1-ADJ (available on the agency's website ). Alternatively, you can simply go the website and make changes to your return through their electronic service.

What you need; and where to go (if you go in person)

Don't forget to include your Social Insurance Number or Identification Number. If you want to discuss your return or assessment in person you may bring your own copy of the return and assessment to your Tax Services Office. If you think the return actually filed is necessary, you should get in touch with your Tax Services Office to arrange for them to obtain the file from the Tax Centre—in some cases this may take a fair amount of time.

The official time limits for filing an amendment ...

If you have already received a Notice of Assessment (discussed further on in this article) and did not formally object to it within 90 days of its mailing date, or within one year of the due date of the T1 return to which the assessment relates, whichever is later, you are technically bound by it.

... leave some wiggle room

Happily though, the Canada Revenue Agency's current policy is that you can apply for a change going back 10 years (technically speaking this is under the so-called "fairness package" introduced in the early nineties); but if you apply for a change within three years of your taxation year, the Canada Revenue Agency will normally simply process your adjustment (exceptions may apply where your requested change is in respect of permissive deductions, such as capital cost allowance (i.e., depreciation expenses), or if it is based on a recent court case in which the taxpayer was successful).

In spite of these policies, if you discovered an error in your favour and reported it to the Canada Revenue Agency, but the 90-day/oneyear time limit will expire before a reassessment is received, you may wish to file a Notice of Objection to protect your rights.

Canada Revenue Agency's 'Top 10' tax filing errors

Some years ago, the Canada Revenue Agency compiled a list of the ten most common errors that Canadians make on their tax returns. In order to avoid having to request an adjustment outside of the 90 day/one year time limit, you should, therefore, take a second glance at your return to make sure you don't also fall prey to the following common mistakes:

  1. Making mathematical errors, such as adding and subtracting incorrectly;
  2. Forgetting to reduce income by identifying amounts received for workers' compensation, social assistance payments, and net federal supplements;
  3. Claiming provincial tax credits incorrectly, by not calculating provincial tax credits properly;
  4. Forgetting to indicate pension adjustments. This affects unused registered retirement savings plan deduction room for the next year;
  5. Claiming an incorrect goods and services tax/harmonized sales tax (or "GST/HST") credit, by using incorrect spousal income amounts;
  6. Entering the wrong amount on the lines of the tax return that refer to contributions and overpayments to the Canada Pension Plan, Quebec Pension Plan, and Employment Insurance;
  7. Claiming incorrect amounts as Registered Retirement Savings Plan (or "RRSP") contributions;
  8. Forgetting to claim the basic personal amount;
  9. Claiming the spousal amount incorrectly;
  10. Not claiming, or incorrectly claiming, the age amount.

Other common tax filing errors and omissions

Other miscellaneous errors or omissions to look out for include the following:

  • Failure to pick up credits and/or deduction carry-forward balances from previous years (i.e., expenses related to home workspace, medical expenses, equivalent- to-spouse credits, capital and non-capital losses, etc.);
  • Forgetting to file an RRSP or charitable donation receipt;
  • Not transferring credits to your spouse if you can't use them.

Where to look online for details

The details for making a T1 adjustment are available at the following address:

Notice of Assessment —What to do?

If your Notice of Assessment is unfavourable, the first thing you must do is find out why the Canada Revenue Agency has disallowed a claim or otherwise increased your taxes. If there's a difference between your figures and theirs, it's quite possible that no one has even looked at your return beyond a keypunching clerk. You have a legal right to appeal your case and, more importantly, if you do this properly, you stand a very good chance of winning.

The first place to look is on page 1 of your notice, which is captioned "Explanation of changes and other important information." In the vast majority of cases, this explanation is computer- generated—and much of the "explanation" you find on the page may actually have nothing much to do with the discrepancy.

Human—and other—errors

In fact, at this stage, the vast majority of problems relate to some type of clerical error. If your return has not been prepared via a computer program you may have made an error, or perhaps a Canada Revenue Agency clerk has simply punched in the wrong number. In other cases, there may be problems with the application of installment remittance (e.g., they've applied it to the wrong year or, worse still, a different taxpayer). Other discrepancies: there may be a late filing penalty even though you filed on time, or a manual check of your return did not reveal a receipt.

Searching for an explanation

When reading the Explanation of Changes, look for something that "doesn't ring a bell," especially if there are numbers shown in the particular paragraph.

If, after reading the Explanation of Changes, you still don't know what's going on, then take a look at the "Summary" calculations contained in the notice. On the left-hand side of the page, you will see key "boxes" (data fields) in your tax return, with the Canada Revenue Agency's calculations on the right-hand side of the page. Compare these to your return on a line-by-line basis, and you should be able to zero-in on where the discrepancy is.

Still no luck? Who to phone

If you still don't know what's going on, one option is to call the folks at your Tax Services Office and ask them. (Of course, another option is to go to an accountant). The Notice of Assessment itself provides a phone number to request an "explanation"—even though the Notice of Assessment itself purports to give one.

Don't assume that, when you get through to a live person on the line, you are dealing with an expert on the matter in question. This simply isn't the case. In many cases, the Canada Revenue agency employees who staff the information lines may not have particular expertise in your problem and will certainly not be familiar with your tax return.

The next step

Once you understand the problem and you think that you're in the right, your next step is to contact the Canada Revenue Agency itself. You may do this in writing—by sending your enquiry to the Tax Centre to which you sent your return. Address it to the attention of the Enquiries and Adjustments Division at the address on the front of the notice. Requests by telephone or personal visits should be directed to the Tax Services Office which serves your area.

The Problem Resolution Program

The Notice of Assessment itself indicates that if the problem can't be resolved, you can contact the tax office's "Problem Resolution Program." The phone number is listed in the government pages—there is a separate listing under the name of each Tax Services Office.

Weighing up whether it's best to go in person or write

If the matter is straightforward and in your favour, so that it could be resolved on the spot, a visit to the Tax Services Office may be a good way to go, if you're able to take time off work. You should have your Notice of Assessment and your copy of your return with you. The Canada Revenue Agency official will pull up your return, key in the adjustment and you're finished. This sure beats waiting for weeks for them to respond to a letter. However, if the matter is more complicated, a letter may be a better way to go.

The starting and stopping of collection procedures

Once a Notice of Assessment is received, collection procedures may commence immediately. However, the collection procedures should stop if a Notice of Objection is filed on a timely basis.

One more channel for voicing your objection

Although some people go straight to a Notice of Objection, contacting the Enquiries and Adjustments section will give you an extra "kick" at the Canada Revenue Agency, just in case there's a problem.

Tactics and etiquette for dealing with the Canada Revenue Agency

When contacting the Canada Revenue Agency, I suggest the following:

  • If you write a letter, put "Re: [your name]; [Social Insurance Number] — 2014 Notice of Assessment" prominently at the top of the letter; in most cases, you should state that there has been an incorrect assessment; give the line number, the previous amount, the amount of the adjustment and the revised amount. Don't forget to include your phone number and name and address;
  • Provide any reasons or details and whatever backup documentation may be relevant, even if you have already included it with your tax return. What you want to do is give the Revenue Canada adjuster a "self-contained package" so that he or she can zero in on the problem;

In general, you should keep your correspondence with Revenue Canada factual and to the point. Revenue Canada's interest is in resolving the dispute as quickly as possible. They don't want to hear your life story, or what you think of the government and our tax system. (For the latter, they can read this newsletter.)

Math errors and factual misunderstandings versus differing interpretations of law

The Canada Revenue Agency will, as a matter of standard procedure, reassess returns if the adjustment relates to an error in arithmetic or a misunderstanding of the facts. If your dispute is based upon a different interpretation of the law, you have to file a Notice of Objection.

Bureaucrats are people too: courtesy goes a long way

In many cases, your letter to the Canada Revenue Agency may be sufficient to clear up the matter in your favour. But if it becomes necessary to actually talk to a Canada Revenue Agency auditor, always be courteous and to the point—I am convinced that a great many serious disputes with the Canada Revenue Agency arise because of personality conflicts—where someone draws the ire of a Revenue Canada auditor. Getting along well with the Canada Revenue Agency goes a long way towards success.

Originally published in The TaxLetter, July 2015

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

To print this article, all you need is to be registered on

Click to Login as an existing user or Register so you can print this article.

Samantha Prasad
In association with
Related Video
Up-coming Events Search
Font Size:
Mondaq on Twitter
Register for Access and our Free Biweekly Alert for
This service is completely free. Access 250,000 archived articles from 100+ countries and get a personalised email twice a week covering developments (and yes, our lawyers like to think you’ve read our Disclaimer).
Email Address
Company Name
Confirm Password
Mondaq Topics -- Select your Interests
 Law Performance
 Law Practice
 Media & IT
 Real Estate
 Wealth Mgt
Asia Pacific
European Union
Latin America
Middle East
United States
Worldwide Updates
Check to state you have read and
agree to our Terms and Conditions

Terms & Conditions and Privacy Statement (the Website) is owned and managed by Mondaq Ltd and as a user you are granted a non-exclusive, revocable license to access the Website under its terms and conditions of use. Your use of the Website constitutes your agreement to the following terms and conditions of use. Mondaq Ltd may terminate your use of the Website if you are in breach of these terms and conditions or if Mondaq Ltd decides to terminate your license of use for whatever reason.

Use of

You may use the Website but are required to register as a user if you wish to read the full text of the content and articles available (the Content). You may not modify, publish, transmit, transfer or sell, reproduce, create derivative works from, distribute, perform, link, display, or in any way exploit any of the Content, in whole or in part, except as expressly permitted in these terms & conditions or with the prior written consent of Mondaq Ltd. You may not use electronic or other means to extract details or information about’s content, users or contributors in order to offer them any services or products which compete directly or indirectly with Mondaq Ltd’s services and products.


Mondaq Ltd and/or its respective suppliers make no representations about the suitability of the information contained in the documents and related graphics published on this server for any purpose. All such documents and related graphics are provided "as is" without warranty of any kind. Mondaq Ltd and/or its respective suppliers hereby disclaim all warranties and conditions with regard to this information, including all implied warranties and conditions of merchantability, fitness for a particular purpose, title and non-infringement. In no event shall Mondaq Ltd and/or its respective suppliers be liable for any special, indirect or consequential damages or any damages whatsoever resulting from loss of use, data or profits, whether in an action of contract, negligence or other tortious action, arising out of or in connection with the use or performance of information available from this server.

The documents and related graphics published on this server could include technical inaccuracies or typographical errors. Changes are periodically added to the information herein. Mondaq Ltd and/or its respective suppliers may make improvements and/or changes in the product(s) and/or the program(s) described herein at any time.


Mondaq Ltd requires you to register and provide information that personally identifies you, including what sort of information you are interested in, for three primary purposes:

  • To allow you to personalize the Mondaq websites you are visiting.
  • To enable features such as password reminder, newsletter alerts, email a colleague, and linking from Mondaq (and its affiliate sites) to your website.
  • To produce demographic feedback for our information providers who provide information free for your use.

Mondaq (and its affiliate sites) do not sell or provide your details to third parties other than information providers. The reason we provide our information providers with this information is so that they can measure the response their articles are receiving and provide you with information about their products and services.

If you do not want us to provide your name and email address you may opt out by clicking here .

If you do not wish to receive any future announcements of products and services offered by Mondaq by clicking here .

Information Collection and Use

We require site users to register with Mondaq (and its affiliate sites) to view the free information on the site. We also collect information from our users at several different points on the websites: this is so that we can customise the sites according to individual usage, provide 'session-aware' functionality, and ensure that content is acquired and developed appropriately. This gives us an overall picture of our user profiles, which in turn shows to our Editorial Contributors the type of person they are reaching by posting articles on Mondaq (and its affiliate sites) – meaning more free content for registered users.

We are only able to provide the material on the Mondaq (and its affiliate sites) site free to site visitors because we can pass on information about the pages that users are viewing and the personal information users provide to us (e.g. email addresses) to reputable contributing firms such as law firms who author those pages. We do not sell or rent information to anyone else other than the authors of those pages, who may change from time to time. Should you wish us not to disclose your details to any of these parties, please tick the box above or tick the box marked "Opt out of Registration Information Disclosure" on the Your Profile page. We and our author organisations may only contact you via email or other means if you allow us to do so. Users can opt out of contact when they register on the site, or send an email to with “no disclosure” in the subject heading

Mondaq News Alerts

In order to receive Mondaq News Alerts, users have to complete a separate registration form. This is a personalised service where users choose regions and topics of interest and we send it only to those users who have requested it. Users can stop receiving these Alerts by going to the Mondaq News Alerts page and deselecting all interest areas. In the same way users can amend their personal preferences to add or remove subject areas.


A cookie is a small text file written to a user’s hard drive that contains an identifying user number. The cookies do not contain any personal information about users. We use the cookie so users do not have to log in every time they use the service and the cookie will automatically expire if you do not visit the Mondaq website (or its affiliate sites) for 12 months. We also use the cookie to personalise a user's experience of the site (for example to show information specific to a user's region). As the Mondaq sites are fully personalised and cookies are essential to its core technology the site will function unpredictably with browsers that do not support cookies - or where cookies are disabled (in these circumstances we advise you to attempt to locate the information you require elsewhere on the web). However if you are concerned about the presence of a Mondaq cookie on your machine you can also choose to expire the cookie immediately (remove it) by selecting the 'Log Off' menu option as the last thing you do when you use the site.

Some of our business partners may use cookies on our site (for example, advertisers). However, we have no access to or control over these cookies and we are not aware of any at present that do so.

Log Files

We use IP addresses to analyse trends, administer the site, track movement, and gather broad demographic information for aggregate use. IP addresses are not linked to personally identifiable information.


This web site contains links to other sites. Please be aware that Mondaq (or its affiliate sites) are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of these third party sites. This privacy statement applies solely to information collected by this Web site.

Surveys & Contests

From time-to-time our site requests information from users via surveys or contests. Participation in these surveys or contests is completely voluntary and the user therefore has a choice whether or not to disclose any information requested. Information requested may include contact information (such as name and delivery address), and demographic information (such as postcode, age level). Contact information will be used to notify the winners and award prizes. Survey information will be used for purposes of monitoring or improving the functionality of the site.


If a user elects to use our referral service for informing a friend about our site, we ask them for the friend’s name and email address. Mondaq stores this information and may contact the friend to invite them to register with Mondaq, but they will not be contacted more than once. The friend may contact Mondaq to request the removal of this information from our database.


This website takes every reasonable precaution to protect our users’ information. When users submit sensitive information via the website, your information is protected using firewalls and other security technology. If you have any questions about the security at our website, you can send an email to

Correcting/Updating Personal Information

If a user’s personally identifiable information changes (such as postcode), or if a user no longer desires our service, we will endeavour to provide a way to correct, update or remove that user’s personal data provided to us. This can usually be done at the “Your Profile” page or by sending an email to

Notification of Changes

If we decide to change our Terms & Conditions or Privacy Policy, we will post those changes on our site so our users are always aware of what information we collect, how we use it, and under what circumstances, if any, we disclose it. If at any point we decide to use personally identifiable information in a manner different from that stated at the time it was collected, we will notify users by way of an email. Users will have a choice as to whether or not we use their information in this different manner. We will use information in accordance with the privacy policy under which the information was collected.

How to contact Mondaq

You can contact us with comments or queries at

If for some reason you believe Mondaq Ltd. has not adhered to these principles, please notify us by e-mail at and we will use commercially reasonable efforts to determine and correct the problem promptly.