Effective January 1st, 2013, all corporations must file income tax returns and make estimated and final tax payments electronically. (This does not apply to pass-through corporate entities filing Form 502, i.e. S-Corporations.) This augments the previous requirements to e-file sales and use tax returns and W-2s for 50 or more employees.
More information is available at the VATax website: http://www.tax.virginia.gov/site.cfm?alias=corporateefile
As always, please call or email me if you have any questions.