Python elif: Check Several Conditions in Order

Some decisions have more than two outcomes: a grade can be A, B, C or F; a ticket can be child, adult or senior. elif (short for "else if") lets you check several conditions in order, and runs the block of the first one that is true.

Syntax#

if condition1:
    ...
elif condition2:
    ...
elif condition3:
    ...
else:
    ...            # none of the above

You can have as many elifs as you need. else at the end is optional.

Example: grades#

score = 82

if score >= 90:
    grade = "A"
elif score >= 75:
    grade = "B"
elif score >= 60:
    grade = "C"
else:
    grade = "F"

print(f"Score {score}: grade {grade}")

Score 82: grade B

Python checks top to bottom. 82 >= 90 is false, 82 >= 75 is true, so grade = "B" and the rest is skipped, even though 82 >= 60 is also true.

Trying several scores:

for score in [95, 82, 64, 40]:
    if score >= 90:
        grade = "A"
    elif score >= 75:
        grade = "B"
    elif score >= 60:
        grade = "C"
    else:
        grade = "F"
    print(score, grade)

95 A
82 B
64 C
40 F

Order matters#

Because only the first true condition runs, putting a broad condition first breaks the logic:

score = 95

if score >= 60:
    grade = "C"
elif score >= 75:
    grade = "B"
elif score >= 90:
    grade = "A"

print(grade)

C

95 is greater than 60, so the first branch wins and the others are never checked. Put the most specific (or highest) condition first.

Notice too that the elif score >= 75 line does not need and score < 90. Earlier branches have already caught higher scores.

Ranges: a BMI category#

bmi = 23.4

if bmi < 18.5:
    category = "Underweight"
elif bmi < 25:
    category = "Normal"
elif bmi < 30:
    category = "Overweight"
else:
    category = "Obese"

print(category)

Normal

Without else#

If no condition matches and there is no else, nothing happens. That is fine when "no action" is a valid outcome, but if a variable is only set inside the branches, make sure some branch always runs (usually with else).

Alternative: match (Python 3.10+)#

When you compare one value against several fixed options, match can be clearer than a long elif chain:

day = "sat"

match day:
    case "sat" | "sun":
        print("Weekend")
    case "mon" | "tue" | "wed" | "thu" | "fri":
        print("Weekday")
    case _:
        print("Unknown day")

Weekend

| means "or", and case _ catches everything else, like else. For ranges and complex conditions, stick with if/elif.

Common mistakes#

Practice#

for units in [80, 150, 320]:
    if units <= 100:
        bill = units * 3
    elif units <= 200:
        bill = 100 * 3 + (units - 100) * 5
    else:
        bill = 100 * 3 + 100 * 5 + (units - 200) * 8
    print(units, bill)

80 240
150 550
320 1760

Key takeaway#