Part of the ELS Conditionals Learning Path. Start with the complete conditionals guide, or study the exact area you need below.
Core difference
Use if when the event is uncertain. Use when when you expect the event to happen and are talking about its timing.
Examples
If I see Maria, I’ll tell her. (I may not see her.)
When I see Maria, I’ll tell her. (I expect to see her.)
When I see Maria, I’ll tell her. (I expect to see her.)
Future clauses
After when, English normally uses a present form for future meaning: ✅ When she arrives, we’ll eat. ❌ When she will arrive...
Zero conditional
In general truths, if and when can often both work: If/When I drink coffee late, I can’t sleep.
Continue the Conditionals learning path
Zero ConditionalLearn when and how to use the zero conditional for facts, routines and general truths.First ConditionalMaster the first conditional for real and possible future situations.Second ConditionalUse the second conditional accurately for hypothetical, unlikely and imaginary present or future situations.Third ConditionalLearn the third conditional for unreal past situations, regrets and alternative past results.Mixed ConditionalsUnderstand mixed conditionals when the condition and result refer to different times.Unless, Provided That, As Long As & Other Alternatives to IfGo beyond if: learn unless, provided that, as long as, even if, in case and other conditional linkers.If I Were YouUnderstand why English often says “If I were you” and when “was” is possible.Conditional SentencesFix the conditional errors English learners make most often.Conditionals ExercisesPractise all English conditional forms with targeted questions, corrections and answers.Conditionals TestTest zero, first, second, third and mixed conditionals and identify what to study next.
Test before you move on
Use the diagnostic test to find out whether your problem is form, meaning, time reference or conditional linkers.
Take the Conditionals diagnostic →