TurboTax adds a note in two locations on the MA tax form that says "NOTE: You cannot apportion MA wages as shown on form W-2 when MA is in Box 15" but that is ENTIRELY incorrect. The same apportionment rules remain in effect from 2019. See 830 Mass. Code Regs. 62.5A.3(3)(b)
(3) Massachusetts Source Income for Nonresidents Telecommuting Due to Pandemic-related
Circumstances.
(a) In General. Under M.G.L. c. 62, § 5A(a), income of a nonresident derived from a trade
or business, including any employment, carried on in the Commonwealth is sourced to
Massachusetts. Pursuant to this rule, all compensation received for services performed by
a nonresident who, immediately prior to the Massachusetts COVID-19 state of emergency
was an employee engaged in performing such services in Massachusetts, and who is
performing services from a location outside Massachusetts due to a Pandemic-related
Circumstance will continue to be treated as Massachusetts source income subject to personal
income tax under M.G.L. c. 62, § 5A and personal income tax withholding pursuant to
M.G.L. c. 62B, § 2.
(b) Apportionment Based on Days Spent Working in Massachusetts. Consistent with the
rule set forth in 830 CMR 62.5A.3(3)(a), a nonresident employee who, prior to the
Massachusetts COVID-19 state of emergency, determined Massachusetts source income by
apportioning based on days spent working in Massachusetts in accordance with 830 CMR
62.5A.1(5)(a), must continue to do so based on:
1. the percentage of the employee's work days spent in Massachusetts during the period
January 1 through February 29, 2020 as determined under 830 CMR 62.5A.1(5)(a); or
2. if the employee worked for the same employer in 2019, the apportionment percentage
properly used to determine the portion of employee wages constituting Massachusetts
source income on the employee's 2019 return. For example, if a nonresident employee
is working from home full-time due to a Pandemic-related Circumstance, but during the
period January 1 through February 29, 2020 the employee worked five days a week, two
of those days from an office in Boston and three of those days from home, 40% of the
employee's wages would continue to be Massachusetts source income.
Here's the URL to the law.
https://www.mass.gov/doc/830-cmr-62-income-tax/download I'm quite displeased at having to amend my return. I pay TurboTax to avoid screwups like this. Lesson learned.
