Missing Tracking Number Field in Sales Order

Under Setup > Company > Enable Features > Transactions tab > Shipping & Receiving section > Shipping Label Integration box is not checked.

Customer is generating Tracking #'s outside of NetSuite.

For the Tracking # field to appear under the Shipping tab of Sales Orders > on the associated Item Fulfillment > Packages tab > enter the Tracking # under the Package tracking number column/field > Save

Go back to the Sales Order > Shipping tab > same Tracking # will be populated.