---
title: "Whitby ADU incentive 2026: rules, sizes and deadline"
url: "https://www.jarviscontracting.ca/guides/whitby-adu-incentive"
description: "Whitby refunds additional dwelling unit permit fees for complete applications by 31 December 2026. The rules: 75 m², 4.5 m, $268 to register, the designs."
publisher: "Jarvis Contracting"
dateModified: "2026-10-05"
---
# Whitby's ADU incentive: fees refunded for applications by 31 Dec 2026

By Jarvis Contracting. Published 2026-10-05, updated 2026-10-05.

The Town of Whitby will pay back the permit and related fees on an additional dwelling unit (ADU) if your complete building permit application is in by 31 December 2026 and the unit is registered by 31 March 2027 ([Town of Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/)). The program is funded by the federal Housing Accelerator Fund. A detached ADU in Whitby can be up to 75 m² and 4.5 m tall, and every ADU must be registered for $268, as of October 2026.

## Key takeaways

- Whitby's incentive can reimburse the ADU building permit fee, the registration inspection fee, a curb cut fee, a below-grade entrance fee and education development charges on detached ADUs, for permits issued after 1 April 2024 ([Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/)).
- The application must be deemed complete by 31 December 2026, and the Town asks you to submit "at least two weeks prior", so plan on mid-December at the latest ([Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/)).
- Whitby zoning allows up to three ADUs on a residential lot, four homes in all, with no more than one in an accessory building ([Zoning By-law 1784 s.4(dd)](https://media-003-ca.cdn.govstack.com/whitby-ca/media/orfb0rfx/1784_zoning-by-law_2025_consolidation-accessible.pdf)).
- A detached ADU can have up to 75 m² of gross floor area, stand up to 4.5 m high in residential zones, and sit 1.2 m from interior side and rear lot lines ([By-law 1784](https://media-003-ca.cdn.govstack.com/whitby-ca/media/orfb0rfx/1784_zoning-by-law_2025_consolidation-accessible.pdf)).
- Registration under By-law 8156-25 costs $268, or $534 if the unit is found through a complaint ([Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/)).
- Whitby and Pickering share a catalogue of six pre-reviewed detached ADU designs from 264 to 634 sq ft ([design catalogue](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/whitby-and-pickering-additional-dwelling-unit-regional-design-catalogue/)).

## What does Whitby's ADU incentive pay back?

It reimburses the Town's own fees on the unit, not the cost of building it. The Town lists "the ADU Building Permit Fee, ADU Registration Inspection Fee, Curb Cut Fee, Below Grade Entrance Fee, and Development Charges for Education applicable to detached ADU's" ([Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/)). Minor variance fees are not eligible.

Here's what those fees are, as of October 2026:

| Fee | 2026 amount | Reimbursable? | Source |
|---|---|---|---|
| ADU building permit, alterations (line BGP-10) | $10.65 per m² | Yes | [Schedule N, 2026](https://media-003-ca.cdn.govstack.com/whitby-ca/media/5aqjt5ww/2026-building-permit-fees-schedule-n.pdf) |
| Below-grade entrance or underpinning | $305 flat | Yes | [Schedule N, 2026](https://media-003-ca.cdn.govstack.com/whitby-ca/media/5aqjt5ww/2026-building-permit-fees-schedule-n.pdf) |
| Education development charges, detached ADU | $7,535 per unit (public $4,349, Catholic $3,186) | Yes | [Durham education DCs, May 2026 to April 2027](https://media-002-ca.cdn.govstack.com/pickeringca-009-ca/media/wl4en3hp/developmentcharges_citywide_2026-2027final.pdf) |
| Curb cut | Not printed on the ADU page | Yes | [Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/) |
| ADU registration (By-law 8156-25) | $268 ($534 after a complaint) | The registration inspection fee is listed; the page doesn't say the $268 itself is | [Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/) |
| Minor variance, residential | $1,526 | No | [Whitby minor variance fees](https://media-003-ca.cdn.govstack.com/whitby-ca/media/txxlnw3w/pl-application_minorvariance.pdf) |

Note: amounts from the Town's 2026 schedules as of October 2026; the education DC figure is the Durham per-unit rate, and the Town decides what it reimburses on your file under the incentive agreement.

On a 60 m² basement apartment with a new below-grade entrance, the permit fee at the ADU rate works out to $639 plus the $305 entrance fee (our arithmetic from Schedule N). The bigger number is on detached units: Whitby says Town and Region development charges don't apply to an ADU that meets Ontario Regulation 454/19, but education development charges "would also still apply for all detached ADU's", and those are what the incentive can cover ([Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/)).

## What are the deadlines?

The dates are fixed, and the first one is close. As of October 2026, here's the sequence the Town sets out:

| Step | Deadline | Source |
|---|---|---|
| Permit issued (earliest that qualifies) | After 1 April 2024 | [Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/) |
| Submit the building permit application | At least two weeks before 31 December 2026 | same |
| Application deemed complete | 31 December 2026 | same |
| Sign the incentive agreement | 31 March 2027 | same |
| Register the ADU with the Town | 31 March 2027 | same |
| Repay the incentive if the unit isn't registered | 30 April 2027 | same |

Note: dates from the Town's ADU page as of October 2026; if the program changes, the Town's page governs.

"Complete" is the word to watch. Under the Ontario Building Code the permit clock starts only once an application has every form, schedule, drawing and fee ([2024 Building Code Compendium](https://www.publications.gov.on.ca/301880)). And if your plan needs a minor variance, Whitby says the decision "must be final and binding when the complete building permit application is submitted" ([Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/)). That means a Committee of Adjustment hearing plus the appeal period, all before December. If you're starting from scratch in October and you need a variance, the incentive may already be out of reach. If your unit fits the zoning as drawn, there's still time, but not much.

## How many units can I add in Whitby, and how big?

Up to three ADUs on a residential lot that permits a detached, semi, link or street townhouse dwelling: two in the house and one in an accessory building, or three in the house ([By-law 1784 s.4(dd)](https://media-003-ca.cdn.govstack.com/whitby-ca/media/orfb0rfx/1784_zoning-by-law_2025_consolidation-accessible.pdf)). That's one more than Ontario's floor of three units on an urban serviced lot, and one more than Pickering allows. On Oak Ridges Moraine and Greenbelt Protected Countryside lots, the limit is one ADU, and none are allowed on Environmental Protection, Natural Heritage System or hazard lands.

For a detached unit in a garage, coach house or backyard building, the zoning sets:

- 75 m² maximum gross floor area (about 807 sq ft);
- 4.5 m maximum height in residential zones;
- 1.2 m from interior side and rear lot lines, 3.0 m from an exterior side lot line;
- an unobstructed path to the ADU entrance at least 1.2 m wide and 2.1 m high;
- one parking space per ADU (a reduced 2.5 m by 5.0 m space and tandem parking are allowed), and none in a Protected Major Transit Station Area.

All from [Zoning By-law 1784](https://media-003-ca.cdn.govstack.com/whitby-ca/media/orfb0rfx/1784_zoning-by-law_2025_consolidation-accessible.pdf), which covers most of Whitby including Brooklin. Downtown Whitby falls under By-law 2585, amended for ADUs by By-law 8142-24, so check that by-law for a downtown lot. The by-law also excludes a detached ADU from the lot's maximum lot coverage, which matters on Whitby's older R1 to R3 lots capped at 20%. Our [Bill 23 units guide](https://www.jarviscontracting.ca/guides/bill-23-additional-units-ontario) compares these limits with Oshawa, Ajax, Pickering, Clarington and the rest of the GTA.

## What are the Whitby and Pickering pre-approved ADU designs?

They're six detached ADU designs that the two towns reviewed ahead of time, funded by the Housing Accelerator Fund. Every one is under Whitby's 75 m² cap:

| Design | Size | Layout |
|---|---|---|
| Bob Abrahams Architect Corp. Model 20P | 264 sq ft | One bedroom, one bathroom |
| AAA Architects Inc. Model 8-2 | 409 sq ft | Studio, one bathroom |
| Jensen Design Services | 450 sq ft | One bedroom, one bathroom |
| AAA Architects Inc. Model 9-4 | 473 sq ft | One bedroom, one bathroom |
| Bob Abrahams Architect Corp. Model 30F | 484 sq ft | One bedroom, one bathroom |
| CMHC Housing Design Catalogue, ADU 01 | 634 sq ft | One bedroom, one bathroom |

Note: from the [Whitby and Pickering design catalogue](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/whitby-and-pickering-additional-dwelling-unit-regional-design-catalogue/) as of October 2026; the catalogue doesn't publish a price for the plans.

A catalogue design saves design time; it doesn't skip the permit. The catalogue says "Building permits will be reviewed based on site-specific conditions", and the site plan and the "applicable foundation and HVAC plans" are bought from the designers. You still need a site plan that shows the setbacks and the 1.2 m path, the servicing route for water, sewer and power, and a foundation that suits your soil. The designs top out at one bedroom, so for a two-bedroom unit you're drawing your own within the 75 m².

## Do I need to register a Whitby ADU, and what else applies?

Yes. Whitby requires every ADU to be registered with the Town under By-law 8156-25, on top of the building permit, for $268 ([Whitby ADU page](https://www.whitby.ca/services-and-payments/building-and-renovating/additional-dwelling-units/)). It's $534 if the unit comes to light through a complaint, and $107 to transfer a registration. The Town's FAQ lists prosecution, voided insurance and liability as the risks of a non-compliant unit.

Whitby also lies in the Central Lake Ontario Conservation Authority (CLOCA) watershed, and CLOCA says new structures and additional dwelling units in its regulated areas near streams, wetlands and the shoreline need its permit ([CLOCA](https://www.cloca.com/inquiries-permits)). And a basement apartment has to meet the Ontario Building Code's rules for a second unit, which our [legal basement requirements guide](https://www.jarviscontracting.ca/guides/legal-basement-apartment-requirements-ontario) sets out.

## Where we come in

We're based in Ajax, next door to Whitby, and we draw permit drawings in-house, so we can take a basement apartment, a garage conversion or a backyard unit from a measured drawing to a permit application without waiting on an outside designer. With the December deadline, that's the part that matters most. If you've bought a catalogue design, we can prepare the site-specific drawings around it and build it. See our garden suites page and [basement renovations page](https://www.jarviscontracting.ca/basement-renovations) for how we approach each, and our [legal basement cost guide](https://www.jarviscontracting.ca/guides/legal-basement-apartment-cost-ontario) for what the build itself tends to cost.

## Questions

### What is Whitby's additional dwelling unit incentive?

Whitby's additional dwelling unit incentive is a Housing Accelerator Fund program that reimburses the Town's ADU fees: the ADU building permit fee, registration inspection fee, curb cut fee, below-grade entrance fee and education development charges on detached ADUs. It applies to permits issued after 1 April 2024 with a complete application by 31 December 2026.

### What is the deadline for Whitby's ADU incentive?

The ADU building permit application must be deemed complete by 31 December 2026, and Whitby asks for submissions at least two weeks before that. The unit must be registered and the incentive agreement signed by 31 March 2027, or the money is repayable by 30 April 2027.

### How big can a detached ADU be in Whitby?

A detached additional dwelling unit in Whitby can have up to 75 m² of gross floor area and be up to 4.5 m high in residential zones, with 1.2 m interior side and rear setbacks and 3.0 m on an exterior side, under Zoning By-law 1784 as of October 2026.

### How many additional dwelling units are allowed in Whitby?

Whitby allows up to three additional dwelling units on a residential lot, for four homes in total, with no more than one in an accessory building. Lots on the Oak Ridges Moraine or in the Greenbelt Protected Countryside are limited to one.

### Does Whitby charge development charges on an ADU?

Whitby says Town and Region development charges don't apply to an ADU that meets Ontario Regulation 454/19. Education development charges still apply to detached ADUs, currently $7,535 per unit in most of Durham Region, and the incentive can reimburse them.

### Can I use the Whitby and Pickering pre-approved ADU designs?

Yes. The Towns of Whitby and Pickering publish six pre-reviewed detached ADU designs from 264 to 634 sq ft. You buy the plans from the designer, and the building permit is still reviewed against your lot's site-specific conditions.