diff --git a/sites/backend/openapi/users.mjs b/sites/backend/openapi/users.mjs
index d109320b24f..60dc5fcf18a 100644
--- a/sites/backend/openapi/users.mjs
+++ b/sites/backend/openapi/users.mjs
@@ -514,3 +514,52 @@ paths['/users/{username}'] = {
     },
   },
 }
+
+// Check whether a username is available
+const checkUsername = "Little Miss Can't Be Wrong"
+paths['/available/username'] = {
+  post: {
+    tags: ['Users'],
+    summary: `Checks whether a username is available`,
+    description:
+      'This allows a background check to see whether a username is available during signup',
+    requestBody: {
+      required: true,
+      content: {
+        'application/json': {
+          schema: {
+            type: 'object',
+            properties: {
+              username: {
+                type: 'string',
+                description: 'The username to check for availability',
+                example: checkUsername,
+              },
+            },
+          },
+        },
+      },
+    },
+    responses: {
+      200: {
+        description:
+          '**Success - Username is NOT available**\n\n' +
+          'Status code `200` indicates that the username exists.',
+        ...jsonResponse({
+          result: 'success',
+          username: checkUsername,
+          available: false,
+        }),
+      },
+      401: response.status['401'],
+      403: {
+        ...response.status['403'],
+        description:
+          response.status['403'].description +
+          errorExamples(['accountStatusLacking', 'insufficientAccessLevel']),
+      },
+      404: response.status['404'],
+      500: response.status['500'],
+    },
+  },
+}
diff --git a/sites/backend/src/controllers/users.mjs b/sites/backend/src/controllers/users.mjs
index b1880f0ef44..872e92a640b 100644
--- a/sites/backend/src/controllers/users.mjs
+++ b/sites/backend/src/controllers/users.mjs
@@ -78,3 +78,23 @@ UsersController.prototype.updateMfa = async (req, res, tools) => {
 
   return User.sendResponse(res)
 }
+
+/*
+ * Checks whether a submitted username is available
+ *
+ * See: https://freesewing.dev/reference/backend/api
+ */
+UsersController.prototype.isUsernameAvailable = async (req, res, tools) => {
+  const User = new UserModel(tools)
+  await User.find(req.body)
+
+  if (User.exists)
+    User.setResponse(200, false, {
+      result: 'success',
+      username: req.body?.username,
+      available: false,
+    })
+  else User.setResponse(404)
+
+  return User.sendResponse(res)
+}
diff --git a/sites/backend/src/models/apikey.mjs b/sites/backend/src/models/apikey.mjs
index d3c29ba45a7..e3e36614d6c 100644
--- a/sites/backend/src/models/apikey.mjs
+++ b/sites/backend/src/models/apikey.mjs
@@ -52,7 +52,7 @@ ApikeyModel.prototype.guardedRead = async function ({ params, user }) {
   if (user.iss && user.status < 1) return this.setResponse(403, 'accountStatusLacking')
 
   await this.unguardedRead({ id: params.id })
-  if (!this.record) return this.setResponse(404, 'apikeyNotFound')
+  if (!this.record) return this.setResponse(404)
 
   if (this.record.userId !== user.uid) {
     // Not own key - only admin can do that
@@ -76,7 +76,7 @@ ApikeyModel.prototype.guardedDelete = async function ({ params, user }) {
   if (user.iss && user.status < 1) return this.setResponse(403, 'accountStatusLacking')
 
   await this.unguardedRead({ id: params.id })
-  if (!this.record) return this.setResponse(404, 'apikeyNotFound')
+  if (!this.record) return this.setResponse(404)
 
   if (this.record.userId !== user.uid) {
     // Not own key - only admin can do that
diff --git a/sites/backend/src/models/user.mjs b/sites/backend/src/models/user.mjs
index 40d49ae2ee9..c583d43d205 100644
--- a/sites/backend/src/models/user.mjs
+++ b/sites/backend/src/models/user.mjs
@@ -265,7 +265,7 @@ UserModel.prototype.passwordLogin = async function (req) {
  * Confirms a user account
  */
 UserModel.prototype.confirm = async function ({ body, params }) {
-  if (!params.id) return this.setResponse(404, 'confirmationIdMissing')
+  if (!params.id) return this.setResponse(404)
   if (Object.keys(body) < 1) return this.setResponse(400, 'postBodyMissing')
   if (!body.consent || typeof body.consent !== 'number' || body.consent < 1)
     return this.setResponse(400, 'consentRequired')
@@ -275,20 +275,18 @@ UserModel.prototype.confirm = async function ({ body, params }) {
 
   if (!this.Confirmation.exists) {
     log.warn(err, `Could not find confirmation id ${params.id}`)
-    return this.setResponse(404, 'failedToFindConfirmationId')
+    return this.setResponse(404)
   }
 
   if (this.Confirmation.record.type !== 'signup') {
     log.warn(err, `Confirmation mismatch; ${params.id} is not a signup id`)
-    return this.setResponse(404, 'confirmationIdTypeMismatch')
+    return this.setResponse(404)
   }
 
   if (this.error) return this
   const data = this.Confirmation.clear.data
-  if (data.ehash !== this.Confirmation.record.user.ehash)
-    return this.setResponse(404, 'confirmationEhashMismatch')
-  if (data.id !== this.Confirmation.record.user.id)
-    return this.setResponse(404, 'confirmationUserIdMismatch')
+  if (data.ehash !== this.Confirmation.record.user.ehash) return this.setResponse(404)
+  if (data.id !== this.Confirmation.record.user.id) return this.setResponse(404)
 
   // Load user
   await this.read({ id: this.Confirmation.record.user.id })
@@ -404,12 +402,12 @@ UserModel.prototype.guardedUpdate = async function ({ body, user }) {
 
     if (!this.Confirmation.exists) {
       log.warn(err, `Could not find confirmation id ${params.id}`)
-      return this.setResponse(404, 'failedToFindConfirmationId')
+      return this.setResponse(404)
     }
 
     if (this.Confirmation.record.type !== 'emailchange') {
       log.warn(err, `Confirmation mismatch; ${params.id} is not an emailchange id`)
-      return this.setResponse(404, 'confirmationIdTypeMismatch')
+      return this.setResponse(404)
     }
 
     const data = this.Confirmation.clear.data
@@ -570,6 +568,7 @@ UserModel.prototype.setResponse = function (status = 200, error = false, data =
     this.response.body.result = 'error'
     this.error = true
   } else this.error = false
+  if (status === 404) this.response.body = null
 
   return this.setExists()
 }
diff --git a/sites/backend/src/routes/users.mjs b/sites/backend/src/routes/users.mjs
index ebc85c418b5..c5081fcd988 100644
--- a/sites/backend/src/routes/users.mjs
+++ b/sites/backend/src/routes/users.mjs
@@ -40,6 +40,10 @@ export function usersRoutes(tools) {
   app.post('/account/mfa/key', passport.authenticate(...bsc), (req, res) =>
     Users.updateMfa(req, res, tools)
   )
+
+  // Check whether a username is available
+  app.post('/available/username', (req, res) => Users.isUsernameAvailable(req, res, tools))
+
   /*
 
   // Remove account
@@ -95,11 +99,5 @@ export function usersRoutes(tools) {
     (req, res) => User.readProfile(req, res, params)
   )
 
-  // Check whether a username is available
-  app.post(
-    '/available/username',
-    passport.authenticate('jwt', { session: false }),
-    (req, res) => User.isUsernameAvailable(req, res, params)
-  )
   */
 }
diff --git a/sites/backend/tests/user.mjs b/sites/backend/tests/user.mjs
index 00f353a39e6..b4acc5003e8 100644
--- a/sites/backend/tests/user.mjs
+++ b/sites/backend/tests/user.mjs
@@ -258,4 +258,36 @@ export const userTests = async (chai, config, expect, store) => {
         })
     })
   })
+
+  describe(`${store.icon('user')} Check for available usernames`, () => {
+    it(`${store.icon('user')} Should find a username is available`, (done) => {
+      chai
+        .request(config.api)
+        .post(`/available/username`)
+        .send({
+          username: 'haochi',
+        })
+        .end((err, res) => {
+          expect(err === null).to.equal(true)
+          expect(res.status).to.equal(404)
+          done()
+        })
+    })
+    it(`${store.icon('user')} Should find a username is not available`, (done) => {
+      chai
+        .request(config.api)
+        .post(`/available/username`)
+        .send({
+          username: store.account.username,
+        })
+        .end((err, res) => {
+          expect(err === null).to.equal(true)
+          expect(res.status).to.equal(200)
+          expect(res.body.result).to.equal('success')
+          expect(res.body.available).to.equal(false)
+          expect(res.body.username).to.equal(store.account.username)
+          done()
+        })
+    })
+  })
 }