Unless you reside in a cave (in which case you likely will not be reading this), you are aware that we are moving towards a paperless society.  However, assumptions about providing documents electronically can be dangerous, and privacy rights must also be respected.  With respect to issuing Form W-2, IRS Publication 15-A provides the following:

Furnishing Form W-2 to employees electronically. You may set up a system to furnish Form W-2 electronically. Each employee participating must consent (either electronically or by paper document) to receive his or her Form W-2 electronically, and you must notify the employee of all hardware and software requirements to receive the form. You may not send a Form W-2 electronically to any employee who doesn’t consent or who has revoked consent previously provided. To furnish Forms W-2 electronically, you must meet the following disclosure requirements and provide a clear and conspicuous statement of each requirement to your employees.

• The employee must be informed that he or she will receive a paper Form W-2 if consent isn’t given to receive it electronically.
• The employee must be informed of the scope and duration of the consent.
• The employee must be informed of any procedure for obtaining a paper copy of his or her Form W-2 and whether or not the request for a paper statement is treated as a withdrawal of his or her consent to receiving his or her Form W-2 electronically.
• The employee must be notified about how to withdraw a consent and the effective date and manner by which the employer will confirm the withdrawn consent. The employee must also be notified that the withdrawn consent doesn’t apply to the previously issued Forms W-2.
• The employee must be informed about any conditions under which electronic Forms W-2 will no longer be furnished (for example, termination of employment).
• The employee must be informed of any procedures for updating his or her contact information that enables the employer to provide electronic Forms W-2.
• The employer must notify the employee of any changes to the employer’s contact information.

You must furnish electronic Forms W-2 by the same due date as the paper Forms W-2. For more information on furnishing Form W-2 to employees electronically, see Regulations section 31.6051-1(j).