When I run a transaction report and include settlement date, the field is blank for some transactions.
If a transaction is not showing a settlement date, this is because the transaction has not yet settled. If you also include the field "Settlement Status" you can confirm this as it will say "Unsettled". If you would like to know why your transaction has not settled, please refer to this solution for more information. In addition if you are using BBMS, you should look at this solution as well for possible answers.