To find the perimeter of a rectangle, you can use the formula:
\[ \text{Perimeter} = 2 \times (\text{length} + \text{width}) \]
In this case, the height (or length) of the note card is 4 inches, and the width is 6 inches. Plugging these values into the formula gives:
\[ \text{Perimeter} = 2 \times (4 + 6) = 2 \times 10 = 20 \text{ inches} \]
Therefore, the perimeter of the note card is \( \boxed{20} \) inches.