diff --git a/src/encoding_implementations/ordinal_pattern.jl b/src/encoding_implementations/ordinal_pattern.jl
index 603a62e9..1c106413 100644
--- a/src/encoding_implementations/ordinal_pattern.jl
+++ b/src/encoding_implementations/ordinal_pattern.jl
@@ -68,7 +68,7 @@ function encode(encoding::OrdinalPatternEncoding{m}, χ::AbstractVector) where {
     if m != length(χ)
         throw(ArgumentError("Permutation order and length of input must match!"))
     end
-    perm = sortperm!(encoding.perm, χ)
+    perm = sortperm!(encoding.perm, χ; lt = encoding.lt)
     return permutation_to_integer(perm)
 end
 
diff --git a/test/encodings/encodings/ordinal_pattern_encoding.jl b/test/encodings/encodings/ordinal_pattern_encoding.jl
index c457f199..4df124d1 100644
--- a/test/encodings/encodings/ordinal_pattern_encoding.jl
+++ b/test/encodings/encodings/ordinal_pattern_encoding.jl
@@ -58,7 +58,7 @@ end
     @test missing_outcomes(OrdinalPatterns(; m, τ), x) == 0
 end
 
-@testset "Pretty printing" begin 
+@testset "Pretty printing" begin
     o = OrdinalPatterns{3}()
     @test occursin("OrdinalPatterns{3}", repr(o))
     @test occursin("encoding = OrdinalPatternEncoding(perm = [0, 0, 0], lt = isless_rand), τ = 1", repr(o))
@@ -67,3 +67,12 @@ end
     s = "[OrdinalPatterns{3}(encoding = OrdinalPatternEncoding(perm = [0, 0, 0], lt = isless_rand), τ = 1), OrdinalPatterns{3}(encoding = OrdinalPatternEncoding(perm = [0, 0, 0], lt = isless_rand), τ = 1), OrdinalPatterns{3}(encoding = OrdinalPatternEncoding(perm = [0, 0, 0], lt = isless_rand), τ = 1)]"
     @test occursin(s, repr(os))
 end
+
+@testset "usage of isless" begin
+    o = OrdinalPatternEncoding{2}() # random is less
+    res = [encode(o, [1,1]) for i in 1:1000]
+    @test unique(res) == [1, 2]
+    o = OrdinalPatternEncoding{2}(isless) # random is less
+    res = [encode(o, [1,1]) for i in 1:1000]
+    @test unique(res) == [1]
+end