diff --git a/lib/validations/user.ts b/lib/validations/user.ts
index 2011401439..0c0448c678 100644
--- a/lib/validations/user.ts
+++ b/lib/validations/user.ts
@@ -1,6 +1,8 @@
 import { z } from "zod";
 
+import { checkUsername } from "@calcom/lib/server/checkUsername";
 import { _UserModel as User } from "@calcom/prisma/zod";
+import { iso8601 } from "@calcom/prisma/zod-utils";
 
 import { timeZone } from "@lib/validations/shared/timeZone";
 
@@ -50,14 +52,26 @@ enum timeFormat {
   TWENTY_FOUR = 24,
 }
 
+const usernameSchema = z
+  .string()
+  .transform((v) => v.toLowerCase())
+  // .refine(() => {})
+  .superRefine(async (val, ctx) => {
+    if (val) {
+      const result = await checkUsername(val);
+      if (!result.available) ctx.addIssue({ code: z.ZodIssueCode.custom, message: "already_in_use_error" });
+      if (result.premium) ctx.addIssue({ code: z.ZodIssueCode.custom, message: "premium_username" });
+    }
+  });
+
 // @note: These are the values that are editable via PATCH method on the user Model
 export const schemaUserBaseBodyParams = User.pick({
   name: true,
+  email: true,
+  username: true,
   bio: true,
   timeZone: true,
   weekStart: true,
-  endTime: true,
-  bufferTime: true,
   theme: true,
   defaultScheduleId: true,
   locale: true,
@@ -75,13 +89,12 @@ export const schemaUserBaseBodyParams = User.pick({
 // Here we can both require or not (adding optional or nullish) and also rewrite validations for any value
 // for example making weekStart only accept weekdays as input
 const schemaUserEditParams = z.object({
+  email: z.string().email(),
+  username: usernameSchema,
   weekStart: z.nativeEnum(weekdays).optional(),
   brandColor: z.string().min(4).max(9).regex(/^#/).optional(),
   darkBrandColor: z.string().min(4).max(9).regex(/^#/).optional(),
   timeZone: timeZone.optional(),
-  bufferTime: z.number().min(0).max(86400).optional(),
-  startTime: z.number().min(0).max(86400).optional(),
-  endTime: z.number().min(0).max(86400).optional(),
   theme: z.nativeEnum(theme).optional().nullable(),
   timeFormat: z.nativeEnum(timeFormat).optional(),
   defaultScheduleId: z
@@ -97,13 +110,11 @@ const schemaUserEditParams = z.object({
 
 const schemaUserCreateParams = z.object({
   email: z.string().email(),
+  username: usernameSchema,
   weekStart: z.nativeEnum(weekdays).optional(),
   brandColor: z.string().min(4).max(9).regex(/^#/).optional(),
   darkBrandColor: z.string().min(4).max(9).regex(/^#/).optional(),
   timeZone: timeZone.optional(),
-  bufferTime: z.number().min(0).max(86400).optional(),
-  startTime: z.number().min(0).max(86400).optional(),
-  endTime: z.number().min(0).max(86400).optional(),
   theme: z.nativeEnum(theme).optional().nullable(),
   timeFormat: z.nativeEnum(timeFormat).optional(),
   defaultScheduleId: z
@@ -112,7 +123,7 @@ const schemaUserCreateParams = z.object({
     .optional()
     .nullable(),
   locale: z.nativeEnum(locales).optional(),
-  createdDate: z.string().or(z.date()).optional(),
+  createdDate: iso8601.optional(),
 });
 
 // @note: These are the values that are editable via PATCH method on the user Model,
@@ -120,6 +131,7 @@ const schemaUserCreateParams = z.object({
 export const schemaUserEditBodyParams = schemaUserBaseBodyParams
   .merge(schemaUserEditParams)
   .omit({})
+  .partial()
   .strict();
 
 export const schemaUserCreateBodyParams = schemaUserBaseBodyParams
diff --git a/pages/api/users/[userId]/_patch.ts b/pages/api/users/[userId]/_patch.ts
index dd136a26ee..3f7761c539 100644
--- a/pages/api/users/[userId]/_patch.ts
+++ b/pages/api/users/[userId]/_patch.ts
@@ -59,7 +59,7 @@ export async function patchHandler(req: NextApiRequest) {
   // Here we only check for ownership of the user if the user is not admin, otherwise we let ADMIN's edit any user
   if (!isAdmin && query.userId !== req.userId) throw new HttpError({ statusCode: 403, message: "Forbidden" });
 
-  const body = schemaUserEditBodyParams.parse(req.body);
+  const body = await schemaUserEditBodyParams.parseAsync(req.body);
   const userSchedules = await prisma.schedule.findMany({
     where: { userId: query.userId },
   });
diff --git a/pages/api/users/_post.ts b/pages/api/users/_post.ts
index 268931b122..a8eff743dd 100644
--- a/pages/api/users/_post.ts
+++ b/pages/api/users/_post.ts
@@ -25,7 +25,7 @@ async function postHandler(req: NextApiRequest) {
   const { prisma, isAdmin } = req;
   // If user is not ADMIN, return unauthorized.
   if (!isAdmin) throw new HttpError({ statusCode: 401, message: "You are not authorized" });
-  const data = schemaUserCreateBodyParams.parse(req.body);
+  const data = await schemaUserCreateBodyParams.parseAsync(req.body);
   const user = await prisma.user.create({ data });
   req.statusCode = 201;
   return { user };