diff --git a/src/base.jl b/src/base.jl
index a8165d5..e58342a 100644
--- a/src/base.jl
+++ b/src/base.jl
@@ -152,6 +152,11 @@ size(K::GeneralizedKroneckerProduct, dim::Integer) = size(K)[dim]
 
 Base.copy(K::AbstractKroneckerProduct) = kronecker(copy(K.A), copy(K.B))
 Base.deepcopy(K::AbstractKroneckerProduct) = kronecker(deepcopy(K.A), deepcopy(K.B))
+Base.copy!(K1::AbstractKroneckerProduct, K2::AbstractKroneckerProduct) = begin
+	  Base.copy!(K1.A, K2.A)
+	  Base.copy!(K1.B, K2.B)
+    return K1
+end
 
 Base.similar(K::AbstractKroneckerProduct) = kronecker(similar(K.A), similar(K.B))
 
diff --git a/src/kroneckersum.jl b/src/kroneckersum.jl
index 177d952..f5ceb8b 100644
--- a/src/kroneckersum.jl
+++ b/src/kroneckersum.jl
@@ -14,6 +14,11 @@ end
 Base.copy(K::KroneckerSum) = kroneckersum(copy(K.A), copy(K.B))
 Base.deepcopy(K::KroneckerSum) = kroneckersum(deepcopy(K.A), deepcopy(K.B))
 Base.similar(K::KroneckerSum) = kroneckersum(similar(K.A), similar(K.B))
+Base.copy!(K1::KroneckerSum, K2::KroneckerSum) = begin
+    Base.copy!(K1.A, K2.A)
+    Base.copy!(K1.B, K2.B)
+    return K1
+end
 
 order(M::AbstractKroneckerSum) = order(M.A) + order(M.B)
 issquare(M::AbstractKroneckerSum) = true
diff --git a/test/testbase.jl b/test/testbase.jl
index 22bce9f..290079e 100644
--- a/test/testbase.jl
+++ b/test/testbase.jl
@@ -50,6 +50,12 @@
         @test Kcopy isa AbstractKroneckerProduct
 
         @test similar(K) isa AbstractKroneckerProduct
+
+        if VERSION ≥ v"1.1"
+            Kcopy = similar(A) ⊗ similar(B)
+            @test_nowarn copy!(Kcopy, K)
+            @test Kcopy ≈ K
+        end
     end
 
     @testset "Using vectors" begin
diff --git a/test/testkroneckersum.jl b/test/testkroneckersum.jl
index ddf9fc1..4a6a6e4 100644
--- a/test/testkroneckersum.jl
+++ b/test/testkroneckersum.jl
@@ -24,7 +24,7 @@
 
         @test issquare(KS)
 
-        @test copy(KS) isa KroneckerSum 
+        @test copy(KS) isa KroneckerSum
 
         KScopy = deepcopy(KS)
         @test KScopy ≈ KS
@@ -32,6 +32,12 @@
 
         @test similar(KS) isa KroneckerSum
 
+        if VERSION ≥ v"1.1"
+            KScopy = similar(A) ⊕ similar(B)
+            @test_nowarn copy!(KScopy, KS)
+            @test KScopy ≈ KS
+        end
+
         IC = oneunit(C)
         KS3 = A ⊕ B ⊕ C
         KS3AB = (A ⊕ B) ⊕ C