Blog | National Capital Commission

Redevelopment | National Capital Commission

About Us | National Capital Commission

National Capital Commission | National Capital Commission

Events | National Capital Commission

Event Permits | National Capital Commission

Buildings and walls | National Capital Commission

Greenbelt Master Plan | National Capital Commission

Get Involved | National Capital Commission

All `id` attributes on a page must be unique, or accessible technologies used by the page 
can stop working.

## Example

The duplicate `id` here makes it unclear which label belongs to which input field:

```html
<label for="name">Your name</label>
<input id="name">

<label for="name">Company name</label>
<input id="name">
```

As a result, accessible technologies like screen readers can fail to read out the 
correct text, or may read out no text at all.

Similar issues can occur when using `aria-labelledby` and `aria-describedby`.

## How to fix

Ensure all `id` attributes on a page are unique. 

## More information

See [Technique H93](https://www.w3.org/TR/2016/NOTE-WCAG20-TECHS-20161007/H93) 
for more information.

duplicate-id

March 2026

February 2026

National Capital Commission

Title / URL	Issues
Blog \| National Capital Commissionncc-ccn.gc.ca/blog	2
Redevelopment \| National Capital Commissionncc-ccn.gc.ca/projects/redevelopment	2
About Us \| National Capital Commissionncc-ccn.gc.ca/about-us	2
National Capital Commission \| National Capital Commissionncc-ccn.gc.ca/invented-url-for-404-page	2
Events \| National Capital Commissionncc-ccn.gc.ca/events	2
Event Permits \| National Capital Commissionncc-ccn.gc.ca/business/event-permits	2
National Capital Commission \| National Capital Commissionncc-ccn.gc.ca/	2
Buildings and walls \| National Capital Commissionncc-ccn.gc.ca/projects/buildings-walls	2
Greenbelt Master Plan \| National Capital Commissionncc-ccn.gc.ca/our-plans/greenbelt-master-plan	2
Get Involved \| National Capital Commissionncc-ccn.gc.ca/get-involved	2

Fix duplicate IDs

National Capital Commission

Where this issue has occurred