ILL + STILL = LAUGH
What is this puzzle?
Solve the addition alphametic puzzle where ILL + STILL = LAUGH. Each letter represents a unique digit from 0-9. No number starts with zero.
Difficulty: medium · Category: addition · Unique letters: 8
This medium-level addition alphametic puzzle features 8 unique letters (A, G, H, I, L, S, T, U). In the equation ILL + STILL = LAUGH, each letter maps to a distinct digit from 0 to 9. With only 8 of 10 digits used, 2 digits remain unused in the solution. The leading letters I and S and L cannot represent zero — this is your first constraint. To solve this efficiently, focus on letters that appear in multiple positions across the equation — these are the most constrained and often the easiest to determine first.
- This addition alphametic has 8 unique letters to determine.
- Leading letters: I, S, L. None of these can be zero.
- There are 8 unique letters, so 2 digits from 0–9 will not be used.
- Start from the rightmost column (units place) and work left, tracking carries between columns.
- With two addends, each column can produce a carry of at most 1.
- A moderate number of letters means you'll need logical deduction alongside trial and error.
Play this puzzle
ILL
+
STILL
LAUGH
A=
G=
H=
I=
L=
S=
T=
U=