---
title: UX for fields
description: >-
  Understand the UX guidelines for adding a custom field to checkout to capture
  delivery instructions, and learn how to design the best experience for
  customers and merchants.
source_url:
  html: 'https://shopify.dev/docs/apps/build/checkout/fields-banners/ux-for-fields'
  md: 'https://shopify.dev/docs/apps/build/checkout/fields-banners/ux-for-fields.md'
---

# UX for fields

**Plus:**

[Checkout UI extensions](https://shopify.dev/docs/api/checkout-ui-extensions) that render on the information and shipping and payment steps in checkout are available only to stores on a [Shopify Plus](https://www.shopify.com/plus) plan.

This guide introduces UX guidelines for adding custom fields to checkout.

***

## Placement

A static target lets you define the placement for the extension. Depending on your use case, you might also define multiple static targets to place your extension. For example, you might want to give the option to place the delivery instructions extension either before or after the shipping methods section.

## shopify.extension.toml

```toml
[[extensions.targeting]]
module = "./src/ShippingBefore.jsx"
target =  "purchase.checkout.shipping-option-list.render-before"


[[extensions.targeting]]
module = "./src/ShippingAfter.jsx"
target =  "purchase.checkout.shipping-option-list.render-after"
```

Place the delivery instructions extension in close proximity to the checkout step that it's related to. In this case, the [static targets](https://shopify.dev/docs/api/checkout-ui-extensions/latest/targets) `purchase.checkout.shipping-option-list.render-before` or `purchase.checkout.shipping-option-list.render-after` are the best locations for this extension type because it concerns delivery instructions.

**Note:**

In some cases, extensions might not render if the static target being used is tied to an area that isn't rendered for the customer. For example, extensions using the `purchase.checkout.shipping-option-list.render-after` target won't show in a checkout with only digital products, because they won't be shipped.

![An example of where the purchase.checkout.shipping-option-list.render-after target will render, below the shipping options at checkout.](https://shopify.dev/assets/assets/images/apps/checkout/delivery-instructions-render-example-BYqoAfq_.png)

***

## Components

The components to create a custom field to capture delivery instructions depend on the extension's possible states.

The delivery instructions use case can have the following states:

* Checkbox is unchecked
* Checkbox checked, text area then becomes visible
* Text area with value

| Component | Preview | Tips |
| - | - | - |
| [`Checkbox`](https://shopify.dev/docs/api/checkout-ui-extensions/latest/web-components/forms/checkbox) | ![The checkbox component with a label beside it that says 'Provide delivery instructions'](https://shopify.dev/assets/assets/images/apps/checkout/delivery-instructions-checkbox-example-D1ceLhic.png) | N/A |
| [`Text area`](https://shopify.dev/docs/api/checkout-ui-extensions/latest/web-components/forms/text-area) | ![The text area component with ghost text inside it that says 'Delivery instructions'](https://shopify.dev/assets/assets/images/apps/checkout/delivery-instructions-textfield-example-Bgv74Dhb.png) | Only show this component when the customer has expressed interest in adding delivery instructions. |

***

## Layout

You can stack the checkbox and text area components in the stack component.

| Component | Preview |
| - | - |
| [`Stack`](https://shopify.dev/docs/api/checkout-ui-extensions/latest/web-components/layout-and-structure/stack) | ![A stacked checkbox and text area demonstrating stack](https://shopify.dev/assets/assets/images/apps/checkout/delivery-instructions-blockstack-example-CU1R91tv.png) |

### Stack

In the following example, `base` is the spacing value between the checkbox and text area components. It prevents the extension from being too cramped or too spacious.

![An example of a stack with base spacing.](https://shopify.dev/assets/assets/images/apps/checkout/ux-guidelines/stack-spacing-DPjUzO3a.png)

![An example of a checkbox and text area with base spacing.](https://shopify.dev/assets/assets/images/apps/checkout/delivery-instructions-blockstack-example-CU1R91tv.png)

***

## UX guidelines

Adhere to the following guidelines when you're designing a delivery instructions use case for checkout UI extensions, so that you can help merchants gain customer trust and provide a great checkout experience:

### Reveal information progressively and strategically

Display a simplified state of the extension by default. In the following example, the customer can choose to add delivery instructions to an order. If the customer chooses to add delivery instructions, then the text area component is displayed. It doesn't display otherwise.

![An example of how to use custom fields to capture delivery instructions progressively by revealing information with a checkbox](https://shopify.dev/assets/assets/images/apps/checkout/delivery-instructions-do-dont-vaaqoCXb.png)

### Capture and remember customer inputs

Preserve inputs through the experience. For example, if the customer writes their delivery instructions in the text area component, then unchecks the checkbox component and checks it again, the instructions should still display rather than having the customer type them again.

***

## Next steps

* Explore [UX guidelines](https://shopify.dev/docs/apps/build/checkout/ux-for-checkout) for the entire checkout experience.

- For practical guidance on how to design a user interface for the Shopify admin, refer to Shopify's [App Design Guidelines](https://shopify.dev/docs/apps/design-guidelines).
- Get familiar with Polaris [accessibility](https://polaris.shopify.com/foundations/accessibility) and [content](https://polaris.shopify.com/content/merchant-to-customer) guidelines.

***