Yes our W2 Mate software support W2 Electronic Filing with the state of Oklahoma..
How to e-File Oklahoma W2 Tax Forms Electronically with the OkTAP?
Step # 1. Under the Company General Information tab inside W2 Mate, make sure to enter "OK" for the State field and to enter the employer Oklahoma state ID under "Employer State ID".
Step # 2. Very Important: On the W2 Forms make sure box 15 state and state ID are populated properly.
To be sure, please use the "Update Box 15" feature inside W2 Mate (select "Tools > Update Box 15 for Multiple Employees" from the top menu inside W2 Mate).
Select "OK" under "New State" and enter your Oklahoma employer state ID under "New Employer State ID number"
Hit the "Select All" button to select all employees.
Hit the OK button to apply your changes.
Please make sure to do this step even if you think Box 15 is populated properly on the W2 Forms.
Step # 3. From the top menu inside W2 Mate select E-Filing > W2 Forms.
Step # 4. In the e-File W2 Forms dialog you select "STATE" under "Federal or State" and select Oklahoma as the state name.
Step # 5. Make sure you follow Oklahoma file naming rules:
(001 = file sequence number, 2016 = Tax Year, 999999999 = YOUR FEIN)
Step # 6. Now W2 Mate will create the W2 e-File and will show a list of the employees included in the output file. Double check this information.
Step # 7. Now you need to upload the Oklahoma W2 efile to OkTAP.