4D Shipping SDK 2020 .NET Edition

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IdentifierType Property

Type of shipment identifier by which the shipment is to be tracked.


public UpstrackIdentifierTypes IdentifierType { get; set; }

enum UpstrackIdentifierTypes { uitPackageTrackingNumber, uitMasterTrackingNumber, uitReferenceNumber, uitShipmentBookmark }
Public Property IdentifierType As UpstrackIdentifierTypes

Enum UpstrackIdentifierTypes uitPackageTrackingNumber uitMasterTrackingNumber uitReferenceNumber uitShipmentBookmark End Enum

Default Value



This is required to be provided in a track request.

Possible values are as follows:

Value Type Description
uitPackageTrackingNumber (0) Package Tracking Number
uitMasterTrackingNumber (1) Shipment Tracking Number
uitReferenceNumber (2) Customer Reference Number
uitShipmentBookmark (3) Shipment Bookmark (applicable to Freight shipments only)

To limit the number of tracking replies for a specific reference, you can provide a date range (ShipDateStart and ShipDateEnd) in the request.

When the track request has been made for an identifier of type other than Tracking Number, either the ShipperAccountNumber or the CountryCode and ZipCode (where applicable) are required to be provided in the request.

Tracking by Tracking Number:

UPS uses tracking numbers to identify and track every package as it moves through the UPS system to its destination. You can use this tracking number to track, locate, and verify arrival of a package.

A successful query by tracking number returns the single package within a shipment identified by the tracking number. For example, if a shipment contained four packages, the query response would show a shipment containing the one package out of four with the associated tracking number.

Tracking numbers are available up to 18 months after delivery and UPS makes every effort to ensure that a tracking number uniquely identifies a package during this time period. However, it is possible that a tracking number may be reused within a shorter time period. If this occurs, a query by tracking number returns all packages matching the tracking number.

Tracking by Master Tracking Number:

The Master Tracking Number is the shipment tracking number and identifies that whole shipment.

A successful query by Master Tracking Number returns all of the packages within a shipment. For example, if a shipment contained four packages, the query response would show all four packages.

Tracking by Reference Number:

The Reference Number identifies an individual package or the whole shipment (this must be alphanumeric). These are available up to 6 months after delivery.

The ability to track any UPS package by reference number gives you added flexibility and convenience. When you ship a package, you can assign a customized reference number that you use to coordinate with your billing or filing system. This reference number could be a purchase order number, job number, or a group of words identifying a shipment. You can assign a reference number to an individual package or to all packages in a shipment. A reference number contains any combination of letters and numbers up to 35 characters and is assigned by the customer when shipping data are uploaded electronically to UPS.

A successful query by reference number returns all of the packages within a shipment identified by the reference number. For example, if a shipment contained four packages, and two of the packages were tagged with the reference number "10 widgets", the query response would show a shipment containing those two packages. Since reference numbers are assigned by the customer, UPS cannot guarantee the uniqueness of a reference number across all packages shipped through the UPS system.

To resolve this ambiguity and to narrow down the search, the track request may contain any of the following optional qualifiers:

  • Pickup date range via the ShipDateStart and ShipDateEnd; this way, you can narrow a search to the dates closer to a shipment. The default is 30 days before today's date.
  • Shipper's UPS account number via the ShipperAccountNumber which distinguishes a shipment from other shipments.
  • Destination postal and country code: via the ZipCode and CountryCode.

Tracking by Candidate Bookmark:

During tracking by tracking numbers or reference numbers, it is possible that duplicate shipments will be found. If duplicate shipments are found, then a candidate summary with a corresponding bookmark for each of the shipments will be returned in the response (stored in the ShipmentBookmark. This value can be passed back to a separate track request to retrieve tracking information about the particular shipment of interest.

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4D Shipping SDK 2020 .NET Edition - Version 20.1 [Build 8435]