Business scenarios

1. Let's say you want your lookup field to display only active accounts in the Deals module. Accordingly, you can create a lookup filter condition like  [Business Active] + [is] + [Selected] .
   
   During deal creation, when the sales rep looks for accounts, only the active ones will be displayed.
   This way, the sales rep doesn't need to rummage through an exhaustive list of records to select the active accounts.
2. Again, let's say an academy's Students module features a lookup field called Course, and the academy wants to associate students with active courses only, and not inactive ones. They can do so by applying a filter to show only active courses in the lookup field.

Feature availability

1. Enterprise editions and above
   

Adding lookup filters

1. Go to Setup > Customization > Modules and fields .
   
2. Select a module and a layout.
   
3. Click Edit layout .
   
4. In the layout, select a lookup field and click the More icon.
   Drag and drop a lookup field from the New Fields tray.
5. Click Edit Properties .
   
6. In the Lookup Properties popup, check Filter lookup records .
   
   
7. Select the desired field and the corresponding value.
   Click the plus sign (+) to add one or more criteria.
   
   
8. Click Save.
   
9. Check Validate lookup filter during record edit, if required.
   
   You can use this option when a user applies the lookup filter to the lookup field for the first time, and while the user already has records associated in the lookup field and wants to validate them while editing the record.
10. Click Done .

Points to remember  

1. Lookup filters are module-specific - The lookup filter applied to a field will be automatically applied for all layouts within a particular module if the field is present in those layouts.
   The filter is supported in modules where the lookup and user lookup field is present.
2. Record conversion -  Lookup filters are not validated when records are created via conversion. However, after conversion—if such a record is edited—the system will prompt the user to make changes to match with the lookup criteria.
   You can prevent this by setting the same lookup criteria in both the Leads and Contacts modules or the Accounts or Deals modules, as well as in the case of the Quotes, Sales Orders, and Invoices modules.
3. Validate lookup filter during record edit - Whenever a record is updated and saved, the system usually validates all data present in each field. However, in this case, the existing values of the lookup fields won't be validated, unless the option is enabled.
   
4. Supported fields - Lookup filters can be used for any lookup , user lookup , or  subform lookup fields.
   
5. During import, data from the lookup field will be imported only if it matches the filter criteria configured in the module. If the criteria doesn't match, the value will not be imported.
   
6. If a record is created using a workflow rule, lookup filter validation will not be carried out. Hence, we recommend not using a lookup field that has a filter in workflow rules to create a record.