Custom number format with leading letters and numbers

Sarah82,

Adding to answer by Rob_Elliott:

If you have some rows with no value in this number column, above JSON will return value like INC000 for all rows: 

So instead of it, use this JSON: 

{
  "$schema": "https://developer.microsoft.com/json-schemas/sp/v2/column-formatting.schema.json",
  "elmType": "div",
  "txtContent": "=if(@currentField, 'INC'+padStart(toString(@currentField),3,'0'), '')"
}

Output: 

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