Keeping our CRM free from duplicate contacts is an industry best practice – it helps prevent mismatched records, skewed data analytics and lessens our team confusion. Even better, it means less time spent on administrative tasks and more on actual selling. Merge Duplicate Accounts will be available for All Editions except Database.com for Business accounts and Enterprise, Performance, Unlimited, and Developer Editions for Person accounts.

Merge duplicate accounts in Salesforce classic :

Step-1: Go to Accounts tab and click Merge Accounts in the Tools section as per the below image. If we can’t see it, ask permission from our admin account.

Step-2: Then enter a search string to find potential duplicate accounts and list will show accounts that start with our search string.

Step-3: Then Select up to three accounts we want to merge and click Next.

Step-4: Now we are going to select one account as the master record and then choose the fields that we want to retain from each record.

Step-5: Then click Merge. Finally the Accounts will be merged.

Merge duplicate accounts in Salesforce Lightning Experience :

Step-1: We need to go to a specific account record. If there are potential duplicates, then click View Duplicates to see them. However, it seems only exact same account names are registered as potential duplicates in the Lightning Experience.

Note : If we can’t find the duplicates we want to merge, switch to Salesforce classic and use the Merge Accounts tool.

Step-2: Like how we do it with Salesforce classic, we can choose up to three account records to merge. Then click Next.

Step-3: Similarly, here we need to choose one account record as the master, and choose the field values that we want to keep. Then click Next.

Step-4: Confirm our choices and click on Merge. Now the Accounts will be merged.

Note: We can only merge business accounts or person accounts together. The business accounts and person accounts can’t be mixed.

Reference :
Merge Duplicate Accounts in Salesforce Classic

Merge Duplicate Accounts in Lightning Experience

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