Which code goes in T4 box 45 for employer dental benefits?
T4 box 45 takes one code for the dental coverage the employer offered on December 31: 1 for none, 2 for the employee only, 3 for the employee, spouse and dependent children, 4 for the employee and spouse, 5 for the employee and children. Starting with 2025 slips, the box can never be left blank, even for code 1.
Which code goes in box 45 for each level of coverage?
Box 45 asks whether the employee or any of their family members were eligible, on December 31 of the slip year, to access any dental insurance or coverage of dental services that you offered. It has been mandatory since the 2023 calendar year canada.ca.
| Code | Who could access dental coverage you offered on December 31 |
|---|---|
| 1 | No one: not eligible for any dental insurance or coverage of any kind |
| 2 | The employee only |
| 3 | The employee, their spouse and dependent children |
| 4 | The employee and their spouse |
| 5 | The employee and their dependent children |
The CRA says the codes cover plans where the employee shares the cost, health spending accounts and opt in dental benefits canada.ca. The Health Canada version of the list reads "spouse or common law partner" wherever the CRA says spouse
canada.ca.
The law behind the box defines family member as the employee's spouse or common law partner, a child under 18 (including the partner's child), and a child 18 or older who depends on the employee because of a mental or physical infirmity laws-lois.justice.gc.ca. The obligation is in section 4 of the Dental Care Measures Act, and section 6 says the information is collected for the Canadian Dental Care Plan, not for the Income Tax Act.
Which code applies in the situations payroll gets wrong?
The test is the coverage offered on December 31, so enrollment choices, opt outs and claims history never change the code. These are the cases the CRA spells out.
| Situation on December 31 | Code to use |
|---|---|
| Employee declined, opted out of or never used the plan | The level offered (2 to 5) |
| Employee left before December 31 and is no longer eligible | 1 |
| Health spending account or allowance that covers dental services or insurance | The level it covers (2 to 5) |
| Health spending account or allowance with no dental coverage | 1 |
| Access to an employer negotiated group rate | The level of that access (2 to 5) |
| Plan run by a union with no employer or pension plan involvement | Not reported by the employer for that plan |
| Employer pays a union to deliver the plan, or sponsors it under a collective agreement | The level offered (2 to 5) |
| Overflow T4 for more than six other information codes | Same code on every slip for that employee |
Every row comes from the CRA's box 45 instructions canada.ca. Two more rules catch bureaus: a third party that prepares T4 slips for clients must get the coverage details from the client and complete the box, and an employee with slips under several RP accounts of one business number gets consistent reporting of the December 31 coverage on all of them, unless you choose to report each RP account separately.
How do five employees on one dental plan end up with three different codes?
Say your client runs an office whose dental plan offers full time staff an employee, spouse and children tier. You are preparing the 2026 T4 slips.
| Employee | Facts on December 31, 2026 | Code |
|---|---|---|
| Priya, full time | Enrolled in single coverage only | 3 |
| Marc, full time | Opted out because his spouse's plan covers the family | 3 |
| Lee, part time | Plan terms exclude part time staff, no spending account | 1 |
| Dana | Left in August 2026, coverage ended with the job | 1 |
| Sam, seasonal | $500 health spending account limited to his own dental costs | 2 |
Priya and Marc both get code 3 because that is the level offered to them, whatever they chose. Dana gets code 1 even though she had family coverage for most of the year, because only December 31 counts. Sam's spending account covers dental costs, so it is access at the level it covers.
Now say the payroll software left Lee and Dana blank and coded Marc as 1 because he opted out. That is three violations, and at $100 each the client is exposed to $300 laws-lois.justice.gc.ca. On a 40 person payroll where the field was never set up, the same math reaches $4,000. The 2026 slips are due March 1, 2027 (see T4 slip deadline).
Can box 45 still be left blank for code 1?
No. Under a Health Canada administrative policy, box 45 could be left blank when code 1 applied, but only for the 2023 and 2024 calendar years and only where all reasonable efforts had been made to comply canada.ca. For 2025 slips (filed in early 2026) and 2026 slips, every T4 needs a code, and an employer with no dental plan at all enters 1.
Health Canada lists three ways to fail: not completing the box, removing it from the slip, and reporting the wrong code, each risking a penalty of $100 per incorrect T4 or T4A canada.ca. Under section 8 of the Act, the Minister of Health imposes it, a knowingly false code is also a violation, and section 9 bars a penalty more than three years after the violation
laws-lois.justice.gc.ca. The Minister can also reduce or cancel a penalty on new facts.
A wrong code also hurts the employee's Canadian Dental Care Plan claim
Box 45 exists for the Canadian Dental Care Plan. To qualify, a person can't have access to private dental coverage through their own or a family member's work or pension plan, and adjusted family net income must be under $90,000. Applicants are told to check box 45 on their T4 (and their spouse's) before confirming they have no access: code 1 means no access through that employer, and codes 2 to 5 mean coverage was offered canada.ca.
If the slip shows access, the applicant may have to prove they no longer have it, even when the slip was wrong. If the proof shows access, they're removed from the plan and may have to repay what the plan paid canada.ca. In an eligibility review the employee has 45 days from the letter to send documents to Health Canada, and you're expected to provide the member eligibility review form or a letter quickly
canada.ca. Coding a family as 1 when it was offered coverage sets them up for exactly that.
Pension payers use T4A box 015 with the same five codes
A pension plan administrator reports the same codes 1 to 5 in box 015 of the T4A. Box 015 is mandatory only when the slip has an amount in box 016 (pension or superannuation), and optional otherwise canada.ca. That follows the Act, which ties the duty to salary and wage payments under ITA 153(1)(a) and pension payments under 153(1)(b)
laws-lois.justice.gc.ca.
The 2023 and 2024 code 1 relief applied to box 015 as well, and the declined coverage, union and overflow slip rules mirror the T4 rules canada.ca. A retiree who opted out of pension dental coverage before December 11, 2023 and can't opt back in may still qualify for the dental plan; opting out after that date doesn't help
canada.ca.
Sources
Does box 45 go anywhere on the employee's tax return?
No. Box 45 has no T1 line and doesn't change income or tax; the Act says the information is collected for the Canadian Dental Care Plan and not for the Income Tax Act laws-lois.justice.gc.ca. For what each box does feed into, see T4 boxes explained.
How do I fix a wrong box 45 code that was already filed?
File an amended T4 with the corrected code; the steps are on T4 amendment. Do it before the employee applies or renews for the dental plan, because Health Canada tells employees who think the code is wrong to contact the employer to confirm or correct it first canada.ca.
Is box 45 a taxable benefit field?
No. Box 45 holds a code from 1 to 5, never a dollar amount, and the employers' guide describes it as whether the employee or their family could access dental coverage you offered on December 31, mandatory for 2023 and later years canada.ca. Any taxable benefit is reported in box 14 and the other information codes; see taxable benefits.
Do I fill in box 45 for an employee whose only coverage is through a union plan?
Only if you're involved. A plan the union offers on its own, without the employer or pension plan, isn't reported by the employer; if you engage the union to deliver it, or you sponsor the plan or refund employees under a collective agreement, you report it canada.ca.
General information for the tax year shown, not advice for a specific client. Confirm the facts before you file or remit.