How to prevent a user from creating a new account in Salesforce?

Hi rahul,

You can simply remove Create permission from Account Object on the profile of that user.

Thanks.

Adding some steps:

use this steps may be help you:

Step 1:- Remove the Create permission on the Lead object

Step 2:- Create the Checkbox field on the Lead object (Default=Checked) & Create the checkbox field on the Account object (Default=Unchecked)

Step 3:- Set up the Field mapping between Lead & Account field

Step 4:- Make the Field read only or hide it from the pagelayout

Step 5:- Create the validation rule on Account to block the User to create the Account from scratch or any other source, only exception is for Accounts that getting created from Lead conversion something like this:-

AND(
$Profile.name<>"System Administrator",
Checkbox=False,
ISNEW())

Let me know if you need any help.

Thanks