Affordable Housing Finance, IRC Section 42 LIHTC & Real Estate
LIHTC Section 42 Qualified Basis, DDA Boost & Equity Formula
Calculate IRC Section 42 Low-Income Housing Tax Credit (LIHTC) Boosted Qualified Basis ($M), Annual Tax Credit ($M), 10-Year Credit Allocation ($M), and Syndicated Investor Equity Proceeds ($M).
Strip out land and ineligible soft costs BEFORE applying the 130% QCT/DDA basis boost!
In affordable multifamily development under IRC Section 42, tax-credit equity often funds 50%–75% of total project cost—but two underwriting errors routinely break capital-stack pro formas: first, forgetting to deduct non-depreciable land acquisition, permanent-loan financing fees, and commercial retail space from Total Development Cost when computing Eligible Basis; second, applying the 9% (or 4% bond-financed) credit rate once instead of across the 10-year Section 42 credit stream! Specifically, Boosted_Qualified_Basis = (Total_Dev_Cost - Land_Ineligible) * DDA_Boost * Applicable_Low_Income_Fraction, Annual_Credit = Qualified_Basis * Credit_Rate, and Syndicated_Equity = Annual_Credit * 10 * Syndication_Price_Per_Dollar.
Verify on a 9% Competitive LIHTC Development in a Qualified Census Tract—Total_Dev_Cost = $30.00M (B2), Land_And_Ineligible_Costs = $5.00M (B3 -> Eligible Basis = $25.00M), DDA_Boost_Multiplier = 1.30 (130% QCT/DDA boost, B4), Affordable_Unit_Fraction = 0.80 (80.0% low-income applicable fraction, B5), Annual_Credit_Rate = 0.09 (9.00%, B6), and Syndication_Price = $0.90 per $1.00 of credit (B7): Boosted Qualified Basis equals 25.00 * 1.30 * 0.80 = $26.00M (E2), Annual Tax Credit is 26.00 * 0.09 = $2.34M/yr (E3), 10-Year Total Credit Allocation is $23.40M (E4), and Syndicated Tax-Credit Equity Proceeds equal 23.40 * 0.90 = $21.06M (E5—covering 70.2% of total development cost)!
| IRC §42 LIHTC Capital-Stack Metric ($30M Cost, $5M Land, 1.30x DDA, 80% Low-Inc, 9%) | Formula | Verified Output |
|---|---|---|
| Boosted Qualified Basis ($M) | (Total_Cost - Land_Inelig) * DDA_Boost * Fraction | $26.00M ($20.00M Non-DDA) |
| Annual Section 42 Credit ($M/yr) | Boosted_Qualified_Basis * Credit_Rate | $2.34M ($1.80M Non-DDA) |
| 10-Year Credit Allocation ($M) | Annual_Credit * 10 | $23.40M ($18.00M Non-DDA) |
| Syndicated Equity Proceeds ($M) | 10Yr_Credit_Allocation * Price_Per_Dollar | $21.06M ($16.20M Non-DDA) |
Section 42 Qualified Basis & Syndicated Equity Formula
Validate Total_Cost > 0, 0 <= Land_Inelig < Total_Cost, DDA_Boost in [1.0, 1.3], Applicable_Fraction in (0, 1], Credit_Rate in (0, 0.12], and Syndication_Price in (0, 1.2]!
=LET(dv_c, B2, ln_i, B3, bst, B4, af_f, B5, cr_r, B6, sy_p, B7, IF(OR(dv_c <= 0, ln_i < 0, ln_i >= dv_c, bst < 1, bst > 1.3, af_f <= 0, af_f > 1, cr_r <= 0, cr_r > 0.12, sy_p <= 0, sy_p > 1.2), "Invalid LIHTC Basis Input", ROUND((dv_c - ln_i) * bst * af_f * cr_r * 10 * sy_p, 2)))Non-DDA Tract Gap-Funding Check (Set DDA Boost Multiplier = 1.00)
Change DDA_Boost_Multiplier B4 from 1.30 to 1.00 (a parcel just outside the Qualified Census Tract boundary): Qualified Basis E2 falls from $26.00M to $20.00M, Annual Credit E3 drops to $1.80M, and Syndicated Equity E5 shrinks from $21.06M to $16.20M—opening a $4.86M soft-debt gap!
=IF(ISTEXT(E5), E5, ROUND((B2 - B3) * B4 * B5, 2))Try the example
Use the original values or change them to test your understanding.