The IRS is now allowing online submission of the following third-party authorization forms:
Form 2848 is used to authorize an individual to represent someone before the IRS. The authorized individual must be a person eligible to practice before the IRS. Form 8821 is used to authorize any individual, corporation, firm, organization, or partnership to inspect and/or receive someone's confidential information verbally or in writing for the type of tax and the years or periods listed on the form.
According to the Independent Payroll Providers Association, this new online option "will help payroll professionals remotely obtain signatures from individual and business clients and submit authorization forms electronically."
The IRS has implemented procedures to ensure accuracy and prevent fraud in this process. For example, it gives guidance what constitutes an electronic signatures:
Further details are available on the IRS website.