diff --git a/src/runestone.jl b/src/runestone.jl
index 54dab73..cf5a15a 100644
--- a/src/runestone.jl
+++ b/src/runestone.jl
@@ -285,9 +285,9 @@ function spaces_around_assignments(ctx::Context, node::JuliaSyntax.GreenNode)
     if !(is_assignment(node) && !JuliaSyntax.is_trivia(node))
         return nothing
     end
-    # for-loop nodes are of kind K"=" even when `in` is used so we need to
-    # include K"in" in the predicate too.
-    is_x = x -> is_assignment(x) || JuliaSyntax.kind(x) === K"in"
+    # for-loop nodes are of kind K"=" even when `in` or `∈` is used so we need to
+    # include these kinds in the predicate too.
+    is_x = x -> is_assignment(x) || JuliaSyntax.kind(x) in KSet"in ∈"
     return spaces_around_x(ctx, node, is_x)
 end
 
diff --git a/test/runtests.jl b/test/runtests.jl
index c1aae33..bf254a5 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -159,11 +159,11 @@ end
     @test format_string("a =+ c") == "a = + c"
     # Short form function definitions
     @test format_string("sin(π)=cos(pi)") == "sin(π) = cos(pi)"
-    # For loop nodes are assignment, even when using `in`
-    @test format_string("for i=1:10\nend\n") == "for i = 1:10\nend\n"
-    @test format_string("for i  =1:10\nend\n") == "for i = 1:10\nend\n"
-    @test format_string("for i  =  1:10\nend\n") == "for i = 1:10\nend\n"
-    @test format_string("for i  in  1:10\nend\n") == "for i in 1:10\nend\n"
+    # For loop nodes are assignment, even when using `in` and `∈`
+    for op in ("in", "=", "∈"), sp in ("", " ", "  ")
+        op == "in" && sp == "" && continue
+        @test format_string("for i$(sp)$(op)$(sp)1:10\nend\n") == "for i $(op) 1:10\nend\n"
+    end
 end
 
 @testset "whitespace around <: and >:, no whitespace around ::" begin