WEX Chip / Spec FAQ

Yes, there will be both a magnetic stripe and a chip on the new cards. The mag stripe will be used by those merchants and POS systems that do not yet accept the chip.

Chip cards prevent white plastic or fake card counterfeiting, which benefits the fleet driver, manager, WEX, and accepting merchants.

No, switching to WEX Chip doesn’t remove any existing features.

WEX is switching to chip cards to give our customers enhanced security and additional features and functionality.

WEX began issuing chip cards in Q4, 2020.

There are no format changes to the sales file specification; there are additional values added to the sales file to designate chip card transactions.

WEX has repurposed chargeback reason code 10 to indicate EMV chargebacks.

The terminal action codes are in Table 122 of the 4.1.4 spec (Section 8.6).

WEX’s public keys are available below:
Test
Production

This is not a new BIN, it has been included since the iSpec 2.0, but this is the first time there is a compliance date associated with it. It is defined to match the current BIN 690046.

Until such time that WEX chip is supported at your sites, fallback to magstripe should still be allowed at the pump. Once WEX Chip is supported, fallback to magstripe will no longer be permitted. Fallback at the pump may depend on a merchant’s (or their vendor’s) chip implementation at the site – both at the pump and inside the store:

• Inside – If the WEX chip card cannot be read, the transaction may fall back to magstripe.
• Outside – The customer experience may vary depending on how the site wants to handle fallback. The WEX chip card may fallback to magstripe at the pump or drivers may be directed to see the Cashier inside if the chip card cannot be read at the pump.

Yes, although we prefer standard EMV.

WEX’s requirement is that the merchants use Tag DF39 or Tag 57 (Track 2 Equivalent) to get the PDSN. (Section 3.1.4 of the WEX Spec)

WEX’s requirement is that the merchants use the Tag DF30 or Tag 57 (Track 2 Equivalent) to get the prompting information. (Section 3.1.4 of the WEX Spec)

When the merchant cannot reach the WEX host, chip transactions are limited to the purchase restrictions on DF32 or Tag 57 (track 2 equivalent) which can also be used for the offline purchase restrictions. (Section 3.1.4 of the WEX Spec)

WEX does not use the service code as other major brands do. The WEX technology indicator is in position 33 of Track 2.

The site should recognize that the AID is unknown, the BIN is recognized as not on chip yet, so the transaction is processed using the magnetic stripe. This aligns with the best practices recommended by the US Payments Forum.

No, WEX is using the PURE applet and no changes are required to the kernel for acceptance. Note that some kernels do need updates to read the DF30-DF39 tags, therefore, WEX supports Track 2 Equivalent (Tag 57) so that chip transactions can be processed until those kernels support the chip DF tags.

With WEX Chip for Compliance Release 2, the POS may support Track 2 Equivalent data for the Prompting (DF30), Offline Purchase Restrictions (DF32) and Purchase Device Sequence Number (DF39) tags. Future compliance in late 2022 is proposed for the DF tags.

This is the limit of fuel product dispensed by Type (e.g., unleaded vs. diesel), Quantity, Amount and Unit of Measure on the Preauthorization response in DE62 (Available Products), DE62-1 thru 62-8.

The POS and network must support DE62 for a minimum of the fuel fields. WEX will return a fuel product group code. (Section 5.6.22 of the WEX Spec)

This is the limit for cash, invoice total limit, miscellaneous, additives and repairs on the Preauthorization response in DE62 (Available Products), DE 62-9 thru 62-21. (Section 5.6.22.4 of the WEX Spec)

Although Tag 57 (Track 2 Equivalent) can be used, the following DF tags are proposed for November 1, 2022:

DF30 – Prompting
DF32 – Purchase Restrictions
DF39 – Purchase device sequence number (PDSN)

Also, the following chip tags are included in the WEX Spec and apply to Standard EMV only:

DF34 – Chip Offline Purchase Restrictions Amount for Fuel
DF35 – Chip Offline Purchase Restrictions Amount for non-Fuel.

Card-based flexible prompting, as described in WEX Spec (Section 3.1.1), is also referred to as “Enhanced Prompting”. It includes any prompt combinations read from the magnetic stripe.

Real-time sales completions refer to WEX receiving the completion message of the sale at the time the driver hangs up the nozzle. (Section 3.2.2.4 of the WEX Spec)

WEX requires merchants to send purchase authorizations to WEX for approval/decline. However, when the merchant cannot connect to the WEX host, the merchant should use the purchase restrictions on the card to determine if the products are permitted for purchase.

The terminal should not add products between the preauthorization and completion (the exception is car wash). If WEX hasn’t authorized it, it should not be sold. (This changes if the POS supports DE 62 Available Products in which case they can add items following the processing rules of Available Products.)

If the terminal supports store and forward and is processing a transaction when it cannot reach WEX, then it should limit the items purchased as follows:

• Magstripe is limited to the two digit purchase restriction on the magstripe (Sections 3.1.1 and 3.1.4 of the WEX Spec)

Dollar Shut-off is also called “Partial Authorization”. WEX may return an amount greater than, equal to, or less than the amount requested. A merchant site may lower the amount WEX returns based on local requirements. (Section 4.5.4 of the WEX Spec)

Sales must be done in real time (1200 messages must come up for authorization).

This was removed for Faster EMV (QuickChip). Supporting blocking a chip application applies to Standard EMV only.”

This was removed for Faster EMV (QuickChip). Supporting blocking a chip application applies to Standard EMV only.

Until such time that WEX chip is supported at your sites, fallback to magstripe should still be allowed at the pump. Once WEX Chip is supported, fallback to magstripe will no longer be permitted.