Components

Combo box

Use with caution: Candidate English, Spanish

USWDS v3

A combo box helps users select an item from a large list of options.

Examples

Usage

Choosing the right component for the task

When deciding which component to use, consider the number of options available to the user. The total number of options will determine which component is right for the task:

2 - 5 options: Use Radio button when there are only a few options that can all be exposed at once.
6 - 15 options: Use Select for a limited number of options.
16 - 100 options: Use Combo box, which combines a select with typeahead functionality for easier selection.
101+ options: Use Search input with typeahead to help users quickly find the right option from a large set.

Exceptions to consider when choosing a component

In some cases, exceptions may be considered when choosing the right component:

When the options are known and memorable. Use Combo box if the user will know what to expect as options in the dropdown, such as a list of countries or states. See the USWDS address pattern.
When the radio button labels are long or radio tiles contain descriptive text. Long labels within a dropdown might make it difficult to read and select an option. Radio tiles often include descriptive text that cannot be used in a dropdown. In these cases, Radio button may be the better choice.

Contact the Design System team via #platform-design-system for help if you have other use cases that may be considered exceptions.

Errors

Refer to the specific error example above.

Hint text

Refer to the hint text example above.

Code usage

Attributes and Properties

Property Attribute Type Default Description

disabled disabled boolean false The combo box component will be disabled / read-only.

error error string Error message to display. When defined, this indicates an error.

hint hint string Optional hint text.

label label string Text label for the field.

messageAriaDescribedby message-aria-describedby string An optional message that will be read by screen readers when the select is focused.

name name string Name attribute for the select field.

placeholder placeholder string The placeholder string.

required required boolean false Whether or not this is a required field.

value value string Selected value (will get updated on select).

Events

Name Description

vaSelect The event emitted when the selected value changes

Accessibility considerations

Component checklist

Maturity

Guidance: Examples, usage, code usage, content considerations, and accessibility considerations are all complete.
Research: VFS team conducted research on this component which is linked from this page.
Stability: Component has been in production for more than 3 months with no significant issues found.
Adoption: Multiple teams have adopted this component.

Accessibility

While this component has been previously tested against older criteria, it has not yet been audited with the updated testing criteria.

Code assets

Variations: Storybook includes all variations (style, size, orientation, optional iconography, selection, error state, etc.)
Responsive: Component depicted in all responsive breakpoints.
Interactive states: Includes all interactive states that are applicable (hover, active, focus, keyboard focus, disabled).
Tokens: All design attributes (color, typography, layout, etc.) are available as tokens.
Internationalization: Describes i18n attributes.

Visual assets

Variations: Sketch library includes all variations (style, size, orientation, optional iconography, selection, error state, etc.)
Responsive: Component designed to work in all responsive breakpoints.
Interactive states: Includes all interactive states that are applicable (hover, active, focus, keyboard focus, disabled).
Tokens: All design attributes (color, typography, layout, etc.) are available as tokens.

Combo box

Examples

Default

With default value

With error

Required

With placeholder text

With hint text

With message aria described by