diff --git a/src/ArrowTypes/src/ArrowTypes.jl b/src/ArrowTypes/src/ArrowTypes.jl
index f4f9e39..43c9c10 100644
--- a/src/ArrowTypes/src/ArrowTypes.jl
+++ b/src/ArrowTypes/src/ArrowTypes.jl
@@ -349,7 +349,7 @@
         for i = 2:length(x)
             @inbounds T = promoteunion(T, typeof(toarrow(x[i])))
         end
-        if T === Missing
+        if T === Missing && concrete_or_concreteunion(S)
             T = promoteunion(T, typeof(toarrow(default(S))))
         end
     end
diff --git a/src/ArrowTypes/test/tests.jl b/src/ArrowTypes/test/tests.jl
index d1e1914..71be73e 100644
--- a/src/ArrowTypes/test/tests.jl
+++ b/src/ArrowTypes/test/tests.jl
@@ -164,7 +164,7 @@
     @test eltype(x) == Union{Float64, String}
     @test x == [1.0, 3.14, "hey"]
 
-    @testset "respect non-missing type" begin
+    @testset "respect non-missing concrete type" begin
         struct DateTimeTZ
             instant::Int64
             tz::String
@@ -187,6 +187,13 @@
         # would break this test by returning `Union{Nothing,Missing}`.
         @test eltype(ArrowTypes.ToArrow(Any[missing])) == Missing
     end
+
+    @testset "ignore non-missing abstract type" begin
+        x = ArrowTypes.ToArrow(Union{Missing,Array{Int}}[missing])
+        @test x isa ArrowTypes.ToArrow{Missing, Vector{Union{Missing, Array{Int64}}}}
+        @test eltype(x) == Missing
+        @test isequal(x, [missing])
+    end
 end
 
 end