payloadcms/payload · error · APIError

Collection with slug ${collectionSlug} not found

Error message

Collection with slug ${collectionSlug} not found

What it means

createImport resolves the target collection from req.payload.config.collections by slug. If no registered collection matches collectionSlug, it throws a 400. (Note: the inner `if (!collectionSlug)` is dead code since line 94 already guards the empty-slug case.)

Source

Thrown at packages/plugin-import-export/src/import/createImport.ts:119

  if (debug) {
    req.payload.logger.debug({
      fileName: file.name,
      fileSize: file.data.length,
      mimeType: file.mimetype,
      msg: 'File info',
    })
  }

  const collectionConfig = req.payload.config.collections.find(
    ({ slug }) => slug === collectionSlug,
  )

  if (!collectionConfig) {
    if (!collectionSlug) {
      throw new APIError('Collection slug is required', 400, null, true)
    }
    throw new APIError(`Collection with slug ${collectionSlug} not found`, 400, null, true)
  }

  // Get disabled fields configuration
  const disabledFields =
    collectionConfig.admin?.custom?.['plugin-import-export']?.disabledFields ?? []

  const importHooks = collectionConfig.custom?.['plugin-import-export']?.importHooks

  // Get beforeImport functions for field transformations
  const importFieldHooks = getImportFieldFunctions({
    fields: collectionConfig.flattenedFields || [],
  })

  // Parse the file data
  let originalDocs: Record<string, unknown>[] | undefined
  let documents: Record<string, unknown>[]
  if (format === 'csv') {
    const rawData = await parseCSV({

View on GitHub (pinned to 00c58b35c0)

Solutions

1. Verify collectionSlug exactly matches a slug in payload.config.collections.
2. Log req.payload.config.collections.map(c => c.slug) at the call site to confirm membership.
3. If the collection lives in a plugin, ensure the plugin is added to the config before this runs.

const slugs = new Set(req.payload.config.collections.map((c) => c.slug))
if (!slugs.has(collectionSlug)) {
  throw new Error(`Unknown collection slug: ${collectionSlug}`)
}
await createImport({ collectionSlug, ... })

const isRegisteredSlug = (slug: string, req: PayloadRequest): boolean =>
  req.payload.config.collections.some((c) => c.slug === slug)

When it happens

Trigger: collectionSlug is misspelled, refers to a collection not added to the Payload config, or belongs to a different Payload instance. Also when a collection was renamed but the import caller still uses the old slug.

Common situations: Renaming a collection without updating import config; importing into a collection declared by a plugin that was never installed; copy-paste of a slug from another project.

Related errors

• Collection config not found for: ${importCollection}
• No file data provided for import
• Import file contains ${documents.length} documents but limit
• Import document not found: ${importId}
• Unable to determine mimetype for file: ${importDoc.filename}

AI-assisted analysis of payloadcms/payload@00c58b35c0 (2026-08-12). Data as JSON: /api/errors/a3458198eb7fdd75. Report an issue: GitHub.