diff --git a/packages/domain/src/domain/sap/worksheet/internal_gains.py b/packages/domain/src/domain/sap/worksheet/internal_gains.py
index 5d0e8f35..2f5fb0fb 100644
--- a/packages/domain/src/domain/sap/worksheet/internal_gains.py
+++ b/packages/domain/src/domain/sap/worksheet/internal_gains.py
@@ -34,6 +34,8 @@ from typing import Final, Optional
 _MONTHS_IN_YEAR: Final[int] = 12
 _METABOLIC_GAIN_W_PER_OCCUPANT_COL_A: Final[float] = 60.0
 _LOSSES_W_PER_OCCUPANT_COL_A: Final[float] = -40.0
+_COOKING_W_BASE_COL_A: Final[float] = 35.0
+_COOKING_W_PER_OCCUPANT_COL_A: Final[float] = 7.0
 
 
 def metabolic_monthly_w(*, n_occupants: float) -> tuple[float, ...]:
@@ -57,6 +59,17 @@ def losses_monthly_w(*, n_occupants: float) -> tuple[float, ...]:
                  for _ in range(_MONTHS_IN_YEAR))
 
 
+def cooking_monthly_w(*, n_occupants: float) -> tuple[float, ...]:
+    """SAP 10.2 §5 line (69) — cooking gains in watts per month.
+
+    Table 5 Column A: G_C = 35 + 7 × N watts, constant year-round.
+    Fuel-agnostic (gas vs electric cooker has same heat gain; only the
+    §12 cost calc differentiates).
+    """
+    gain = _COOKING_W_BASE_COL_A + _COOKING_W_PER_OCCUPANT_COL_A * n_occupants
+    return tuple(gain for _ in range(_MONTHS_IN_YEAR))
+
+
 _METABOLIC_W_PER_OCCUPANT: Final[float] = 60.0
 
 
diff --git a/packages/domain/src/domain/sap/worksheet/tests/test_internal_gains.py b/packages/domain/src/domain/sap/worksheet/tests/test_internal_gains.py
index 851da9ef..f6573452 100644
--- a/packages/domain/src/domain/sap/worksheet/tests/test_internal_gains.py
+++ b/packages/domain/src/domain/sap/worksheet/tests/test_internal_gains.py
@@ -13,6 +13,7 @@ Table 5a + Appendix L (lighting/appliances/cooking) + Appendix J Table 1b
 import pytest
 
 from domain.sap.worksheet.internal_gains import (
+    cooking_monthly_w,
     losses_monthly_w,
     metabolic_monthly_w,
 )
@@ -62,3 +63,27 @@ def test_losses_are_negative_40n_constant_across_months() -> None:
     for m, value in enumerate(monthly):
         assert value == pytest.approx(-40.0 * n, abs=1e-9), f"month {m+1}"
         assert value < 0, "Losses must be negative (heat-loss convention)"
+
+
+def test_cooking_gains_match_table_5_col_a_formula() -> None:
+    """SAP 10.2 Table 5 Column A row "Cooking": G_C = 35 + 7 × N watts,
+    constant year-round.
+
+    Cooking gains are fuel-agnostic — the formula applies whether the
+    cooker is gas or electric (fuel matters only for the §12 cost calc,
+    not the internal-gain heat contribution).
+
+    Verified against Elmhurst U985-0001-000490 worksheet (69)m row,
+    which shows 50.0277 W flat. For 000490's N=2.1468:
+        35 + 7 × 2.1468 = 50.0276 W → agrees to 4 d.p.
+    """
+    # Arrange
+    n = 2.1468
+
+    # Act
+    monthly = cooking_monthly_w(n_occupants=n)
+
+    # Assert
+    assert len(monthly) == 12
+    for m, value in enumerate(monthly):
+        assert value == pytest.approx(35.0 + 7.0 * n, abs=1e-9), f"month {m+1}"