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The mortgage interest deduction (MID) is the largest personal tax deduction on the books and is widely considered one of the most sacrosanct tax benefits in the country because it is seen as making homeownership more affordable for middle-class Americans. Our new Reason Foundation research suggests, though, that the average benefits from the MID are not enough to be the difference between renting and home owning for a household.
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If there's a sacrosanct tax benefit in this country, which by the way benefits mostly upper income people who also pay most of the taxes, it's reduced rates of taxation on dividends and long term capital gains, which the Joint Committee on Taxation says costs the federal government $596 billion in lost revenue between 2012 and 2016. The mortgage interest deduction, by contrast, will cost the feds $364 billion. Leave it to Forbes not to mention that.
The mortgage interest deduction may or may not be "the largest personal" deduction, but in the big picture of revenue forfeited by the feds due to tax preferences, which is categorized as "tax loss expenditure", the mortgage interest deduction represents just 6.9% of the revenue lost out of the largest 21 line items in the JCT's report representing $5.25 trillion in tax loss expenditures for the period mentioned (here).
Preferential treatment of income from stocks isn't the biggest preference either (11.4%), but it is much bigger than the preference given to mortgage interest. But businesses do get the biggest preference. When employers provide healthcare contributions, health insurance and long term care insurance, they get to deduct all of that. Cost to the feds? A whopping $706.6 billion (13.5%). And that figure will only grow under ObamaCare.
And how about retirement plan contributions? Cost of excluding both defined benefit and defined contribution plans comes to $505.3 billion over the period (9.6%).
Compared to these, the mortgage interest deduction comes in a distant fourth (in fifth is the earned income tax credit at $319.7 billion).
Compared to these, the mortgage interest deduction comes in a distant fourth (in fifth is the earned income tax credit at $319.7 billion).
The much-maligned charitable deduction, meanwhile, which was the original basis for the standard deduction in the tax code, at $172.4 billion represents just 3.3% of the lost $5.25 trillion in revenue from 2012 to 2016. It comes in fourteenth.
There's lots of things wrong with the world, but changing the home mortgage interest deduction isn't going to fix them. For libertarians to focus on it as they do should tell you there's more going on here than meets the eye: an ideological bias against home ownership because it limits "freedom". Millions beg to differ.