Does M1M Line1 Minnesota Additions incorrectly add (double-dip) rather than checksum its KFLine1 Tax-Exempt Int values to those in 1040Line2a total Tax-Exempt Int?

[burto006]

The same problem last year necessitated paper filing of the state taxes, after TT's online submission was rejected due to "M1 Error Code 0630 - Schedule M1M: the sum of line 1 and line 2 cannot be greater than: line 2a on Form 1040...": The problem them was identical: Two trusts’ beneficiary KFs Lines 1 summed their (“State & municipal bond interest from outside MN”) tax-exempt interest incomes outside of MN as being = $258 + $795 = $1053). That $1053 sum SHOULD have been REPORTED BY TURBOTAX’S CALCULATOR as components of M1M LINE 1’s (& M1 Line 2’s) MN ADDITIONS TO INCOME, AS a $1053 NON-MN SUBSET OF MY TOTAL Federal 1040-SR Line 2a US Tax-exempt Interest (= $1863). But INSTEAD, TURBOTAX ADDED THE NON-MN $1053 SUBSET OF US TAX-EXEMPT INTEREST BACK TO THE TOTAL US TAX-EXEMPT INTEREST OF $1863 (!), MAKING A FALSE, TOO-HIGH MN Income ADDITION OF, NOT THE two MN state KF’s combined income Additions of $1053 NON-US, BUT THE $1053 NON-MN US Tax-exempt INCOME + THE $1863 TOTAL US INCOME (which already includes the $1053 NON-MN Income!) = $2916 in Line 1 of MN State Form M1M. M1M Line 1 (now $2916, when it should be only $1053 from the KF data) is supposed to be LESS THAN 1040 Line 2a ($1863), not GREATER THAN IT (by $1053, the sum of both KF’s Line 1 income additions. This year, ESTIMATED Minnesota Additions in TurboTax Online are already again showing a MN taxable income addition equal to the SUM -- NOT equal to a MN-taxable SUBSET -- of the federal tax-exempt interest income that already includes the MN taxable but federal tax-exempt interest! So MN's TT forms are double-dipping me, although the MN Dept of Revenue will likely again late reject TT's online Minnesota Tax forms with the same error code as last years' rejection. What gives? How can this be user error?

[burto006]

I have an update.

It appears to be a slightly more complex bug than TurboTax's M1M Line 1 doubling its KF Line 1 values: TurboTax's Minnesota (MN) M1M Line 1 since 2023 has apparently been WRONGLY SUMMING 1040 Line 2a (Total Federal Tax-Exempt Interest) WITH MN KF Line 1 (MN-Taxable Other-State Federal Tax-Exempt Interest) to give a FALSELY HIGH M1M Line 1 Minnesota income addition, instead of RIGHTLY SUMMING MN KF Line 1 WITH Other States' K-1 Box 14A (Federal Tax-Exempt Interest) to give the TRUE M1M Line 1 MN income addition, which would be an M1M Line 1 value = to the 1040 Line 2a value MINUS only MN-tax-exempt federal tax-exempt interest).

Consequently, upon TurboTax MN State M1 & M1M E-filing, the submitted M1M Line 1 total (which if calculated correctly represents everything in 1040 Line 2a's Federal Tax-Exempt Interest EXCEPT its small values for MN in-state Tax-Exempt Interest) is then automatically "error checked" by the MN Dept of Revenue to ensure that "M1M Line 1 ≤ 1040 Line 2a" -- and thus the e-filed TurboTax MN tax return is rejected, because it's rightly flagged as showing "M1M line 1 > 1040 Line 2a" for having twice-submitted (thereby doubling MN state income taxes on) any MN KF Line 1 value entered.