---
title: "Update A/B test variant"
method: PATCH
path: "/ab-tests/{abTestId}/variants/{variantId}"
tags: ["A/B Tests"]
---

# Update A/B test variant

`PATCH /ab-tests/{abTestId}/variants/{variantId}`

Updates an A/B test variant's subject, preview text, or body content. Campaign variants remain editable only while the test is in draft. Sequence variants can be edited later with confirmLiveChange when the sequence is active, the test is no longer a draft, or the test has recorded activity; earlier sends remain unchanged, so combined results may no longer be accurate.

## Path parameters

- `abTestId` string, required
- `variantId` string, required

## Request body

- object
  - `html` string — Raw HTML body. Provide either html or blocks, not both.
  - `blocks` EmailBlock[] — Structured email blocks. Provide either blocks or html, not both. Put visual styling under styles; top-level style keys such as backgroundColor, backgroundOpacity, borderColor, borderWidth, and borderRadius are normalized into styles.
    - `id` string
    - `type` 'text' | 'html' | 'heading' | 'list' | 'button' | 'spacer' | 'divider' | 'image' | 'columns' | 'conditional-group' | 'repeat' | 'card' | 'cta' | 'social' | 'logo' | 'header' | 'footer' | 'video' | 'product' | 'discount-code' | 'code' | 'countdown' | 'hero' | 'testimonial' | 'gallery' | 'badge' | 'table' | 'features' | 'image-card' | 'pricing' | 'author' | 'article' | 'rating' | 'stats' | 'steps' | 'product-grid' | 'poll', required
    - `content` string — Content for text, html, and heading-like blocks.
    - `styles` object — Per-block visual styles. For compatibility, style fields such as backgroundColor, backgroundOpacity, borderColor, borderWidth, and borderRadius can also be supplied at the block top level and are normalized into this object.
      - `paddingTop` number
      - `paddingBottom` number
      - `paddingLeft` number
      - `paddingRight` number
      - `backgroundColor` string
      - `backgroundOpacity` number — Background opacity percentage from 0 to 100.
      - `textColor` string
      - `textAlign` 'left' | 'center' | 'right'
      - `borderRadius` number
      - `borderColor` string
      - `borderWidth` number
      - `bleed` boolean — Stretch the block edge-to-edge across the email container. Top-level blocks only.
    - `conditions` object[] — Optional per-block display rules. The block renders only when every rule matches. The same shape is used for a conditional-group block's top-level `conditions`.
      - `id` string, required
      - `field` 'variable' | 'attribute' | 'email' | 'firstName' | 'lastName', required — `variable` resolves a merge-tag path from the transactional send `variables` or an automation `event` payload (nested paths like `order.total` or `event.plan` work). `attribute` reads a stored subscriber attribute. `email`, `firstName`, and `lastName` read core subscriber fields.
      - `operator` 'is' | 'is_not' | 'contains' | 'not_contains' | 'gt' | 'gte' | 'lt' | 'lte' | 'is_empty' | 'is_not_empty', required
      - `value` string, required — For `variable` and `attribute`, use `name:value` - the part before the colon is the variable path or attribute name, and the part after it is the comparison value. For `email`, `firstName`, and `lastName`, provide the plain comparison string.
  - `subject` string
  - `previewText` string, nullable
  - `confirmLiveChange` boolean — Required as true when the sequence is active, the test is no longer a draft, or the test has recorded activity. Earlier sends remain unchanged, so combined results may no longer be accurate.

## Response `200`

Variant updated

- object
  - `success` boolean
  - `variant` ABTestVariant
    - `id` string
    - `variantId` string
    - `abTestId` string
    - `label` string
    - `variantLabel` string
    - `emailId` string
    - `subject` string
    - `previewText` string, nullable
    - `blocks` EmailBlock[]
      - `id` string
      - `type` 'text' | 'html' | 'heading' | 'list' | 'button' | 'spacer' | 'divider' | 'image' | 'columns' | 'conditional-group' | 'repeat' | 'card' | 'cta' | 'social' | 'logo' | 'header' | 'footer' | 'video' | 'product' | 'discount-code' | 'code' | 'countdown' | 'hero' | 'testimonial' | 'gallery' | 'badge' | 'table' | 'features' | 'image-card' | 'pricing' | 'author' | 'article' | 'rating' | 'stats' | 'steps' | 'product-grid' | 'poll', required
      - `content` string — Content for text, html, and heading-like blocks.
      - `styles` object — Per-block visual styles. For compatibility, style fields such as backgroundColor, backgroundOpacity, borderColor, borderWidth, and borderRadius can also be supplied at the block top level and are normalized into this object.
        - `paddingTop` number
        - `paddingBottom` number
        - `paddingLeft` number
        - `paddingRight` number
        - `backgroundColor` string
        - `backgroundOpacity` number — Background opacity percentage from 0 to 100.
        - `textColor` string
        - `textAlign` 'left' | 'center' | 'right'
        - `borderRadius` number
        - `borderColor` string
        - `borderWidth` number
        - `bleed` boolean — Stretch the block edge-to-edge across the email container. Top-level blocks only.
      - `conditions` object[] — Optional per-block display rules. The block renders only when every rule matches. The same shape is used for a conditional-group block's top-level `conditions`.
        - `id` string, required
        - `field` 'variable' | 'attribute' | 'email' | 'firstName' | 'lastName', required — `variable` resolves a merge-tag path from the transactional send `variables` or an automation `event` payload (nested paths like `order.total` or `event.plan` work). `attribute` reads a stored subscriber attribute. `email`, `firstName`, and `lastName` read core subscriber fields.
        - `operator` 'is' | 'is_not' | 'contains' | 'not_contains' | 'gt' | 'gte' | 'lt' | 'lte' | 'is_empty' | 'is_not_empty', required
        - `value` string, required — For `variable` and `attribute`, use `name:value` - the part before the colon is the variable path or attribute name, and the part after it is the comparison value. For `email`, `firstName`, and `lastName`, provide the plain comparison string.
    - `testSends` integer
    - `testOpens` integer
    - `testClicks` integer
    - `isWinner` boolean
    - `localizations` object[]
    - `createdAt` string, date-time
  - `warnings` string[] — Non-blocking advisories about the blocks that were written. The write succeeded. Present when a field was not part of the block schema and was discarded, or when a supported field does not control what its name suggests for that block type - for example styles.backgroundColor on a button colors the band behind the button while the fill comes from buttonColor. Each message names the offending path and the fields that block does accept. A sequence email step update also reports the blocks the step's existing Style > Format added back on top of the submitted blocks, because the response echoes node config rather than the stored blocks. Absent when there is nothing to report.

## Other responses

- `400` — Validation error, immutable non-draft campaign A/B test, or missing live-change confirmation
- `401` — Unauthorized
- `404` — A/B test or variant not found
- `500` — Variant could not be updated

## Changes

- **2026-08-02** `36f92fc0caa2` — 4 breaking
  - the response property `success` became optional for the status `400`
  - the response property `success` became optional for the status `401`
  - the response property `success` became optional for the status `404`
  - the response property `success` became optional for the status `500`
- **2026-07-29** `d03612b5fabd` — 1 info
  - added the optional property `warnings` to the response with the `200` status
- **2026-07-18** `09f0c32988fb` — 1 info
  - added the new optional request property `allOf[subschema #2]/confirmLiveChange`
- **2026-07-16** `d7ea66dede72` — 14 warning, 16 info
  - added the new `article` enum value to the `variant/blocks/items/type` response property for the response status `200`
  - added the new `author` enum value to the `variant/blocks/items/type` response property for the response status `200`
  - added the new `badge` enum value to the `variant/blocks/items/type` response property for the response status `200`
  - added the new `features` enum value to the `variant/blocks/items/type` response property for the response status `200`
  - …26 more
- …earlier changes not shown

[Full history](https://skmtc.dev/sequenzy/apis/sequenzy-api/changes/ab-tests/:abTestId/variants/:variantId/patch.md)

---

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