Create a custom financial dimension
To create a user-defined financial dimension, go to General ledger > Chart of accounts > Dimensions > Financial dimensions in the Use values from field, select Custom dimension.
You can specify an account mask to limit the amount and type of information that can be entered for dimension values. You can enter characters that remain the same for each dimension value, such as letters or a hyphen (-).
You can enter number signs (#) and ampersands (&) as placeholders for characters that will change every time that a dimension value is created. Use a number sign (#) as a placeholder for a number and an ampersand (&) as a placeholder for a letter. The field for the format mask is only available when you select Custom dimension in the Use values from field.
To limit the dimension value to the letters "CC" and three numbers, enter CC-### as the format mask.
Watch this video to learn more about how to create an account structure.