diff --git a/README.md b/README.md
index d083843..4e82a14 100644
--- a/README.md
+++ b/README.md
@@ -41,7 +41,9 @@ DefraRuby::Aws.configure do |config|
       secret_access_key: "SECRET_ACCESS_KEY"
     },
     # optional - Default to "eu-west-1"
-    region: "eu-west-1"
+    region: "eu-west-2",
+    # optional - Default to false. Will use AES256
+    encrypt_with_kms: true
   }]
 end
 ```
@@ -71,6 +73,7 @@ presigned_url = bucket.presigned_url("test-upload-file.csv")
 ```
 
 ### Delete a file from the bucket
+
 ```ruby
 bucket = DefraRuby::Aws.get_bucket("defra-ruby-aws")
 response = bucket.delete("test-upload-file.csv")
@@ -93,7 +96,7 @@ All contributions should be submitted via a pull request.
 
 THIS INFORMATION IS LICENSED UNDER THE CONDITIONS OF THE OPEN GOVERNMENT LICENCE found at:
 
-http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3
+<http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3>
 
 The following attribution statement MUST be cited in your products and applications when using this information.
 
diff --git a/lib/defra_ruby/aws/bucket.rb b/lib/defra_ruby/aws/bucket.rb
index 50a7475..e4221dc 100644
--- a/lib/defra_ruby/aws/bucket.rb
+++ b/lib/defra_ruby/aws/bucket.rb
@@ -3,12 +3,13 @@
 module DefraRuby
   module Aws
     class Bucket
-      attr_reader :bucket_name, :credentials, :region
+      attr_reader :bucket_name, :credentials, :region, :encrypt_with_kms
 
       def initialize(configs)
         @credentials = configs[:credentials]
         @bucket_name = configs[:name]
         @region = setup_region(configs[:region])
+        @encrypt_with_kms = setup_encrypt_with_kms(configs[:encrypt_with_kms])
 
         validate!
       end
@@ -21,6 +22,10 @@ def secret_access_key
         credentials[:secret_access_key]
       end
 
+      def encryption_type
+        @_encryption_type ||= @encrypt_with_kms ? "aws:kms" : :AES256
+      end
+
       def load(file)
         BucketLoaderService.run(self, file)
       end
@@ -47,6 +52,14 @@ def default_region
         "eu-west-1"
       end
 
+      def setup_encrypt_with_kms(encrypt_with_kms)
+        return false if encrypt_with_kms.nil?
+
+        # Handle the argument being either a string or a boolean, or some other
+        # value e.g. "foo"
+        encrypt_with_kms.to_s.downcase == "true"
+      end
+
       def validate!
         validate_presence_of_name!
         validate_presence_of_credentials!
diff --git a/lib/defra_ruby/aws/services/bucket_loader_service.rb b/lib/defra_ruby/aws/services/bucket_loader_service.rb
index 7622e32..f335d8d 100644
--- a/lib/defra_ruby/aws/services/bucket_loader_service.rb
+++ b/lib/defra_ruby/aws/services/bucket_loader_service.rb
@@ -24,7 +24,9 @@ def run
 
       def response_exe
         lambda do
-          s3_bucket.object(File.basename(file.path)).upload_file(file.path, server_side_encryption: "aws:kms")
+          s3_bucket
+            .object(File.basename(file.path))
+            .upload_file(file.path, server_side_encryption: bucket.encryption_type)
         end
       end
     end
diff --git a/spec/lib/defra_ruby/aws/bucket_spec.rb b/spec/lib/defra_ruby/aws/bucket_spec.rb
index 9d673d4..87a7450 100644
--- a/spec/lib/defra_ruby/aws/bucket_spec.rb
+++ b/spec/lib/defra_ruby/aws/bucket_spec.rb
@@ -7,6 +7,8 @@ module Aws
     RSpec.describe Bucket do
       subject(:bucket) { described_class.new(configs) }
 
+      let(:credentials) { { access_key_id: "access_key", secret_access_key: "secret" } }
+
       describe "#initialize" do
         context "when a name configuration is missing" do
           let(:configs) do
@@ -63,16 +65,165 @@ module Aws
             expect { bucket }.to raise_error("DefraRuby::Aws buckets configurations: missing secret access key for bucket foo")
           end
         end
+
+        context "when 'region' is not set" do
+          context "because it has not been added to the config" do
+            let(:configs) do
+              {
+                name: "foo",
+                credentials: credentials
+              }
+            end
+
+            it "defaults the region to 'eu-west-1'" do
+              expect(bucket.region).to eq("eu-west-1")
+            end
+          end
+
+          context "because its value is an empty string" do
+            let(:configs) do
+              {
+                name: "foo",
+                credentials: credentials,
+                region: ""
+              }
+            end
+
+            it "defaults the region to 'eu-west-1'" do
+              expect(bucket.region).to eq("eu-west-1")
+            end
+          end
+        end
+
+        context "when 'region' is set" do
+          let(:region) { "eu-west-2" }
+          let(:configs) do
+            {
+              name: "foo",
+              credentials: credentials,
+              region: region
+            }
+          end
+
+          it "sets the region to match" do
+            expect(bucket.region).to eq(region)
+          end
+        end
+
+        context "when 'encrypt_with_kms' is not set" do
+          context "because it has not been added to the config" do
+            let(:configs) do
+              {
+                name: "foo",
+                credentials: credentials
+              }
+            end
+
+            it "defaults encrypt_with_kms to false" do
+              expect(bucket.encrypt_with_kms).to be false
+            end
+
+            it "sets encryption_type to :AES256" do
+              expect(bucket.encryption_type).to eq(:AES256)
+            end
+          end
+
+          context "because its value is an empty string" do
+            let(:configs) do
+              {
+                name: "foo",
+                credentials: credentials,
+                encrypt_with_kms: ""
+              }
+            end
+
+            it "defaults encrypt_with_kms to false" do
+              expect(bucket.encrypt_with_kms).to be false
+            end
+
+            it "sets encryption_type to :AES256" do
+              expect(bucket.encryption_type).to eq(:AES256)
+            end
+          end
+        end
+
+        context "when 'encrypt_with_kms' is set" do
+          let(:encrypt_with_kms) { true }
+          let(:configs) do
+            {
+              name: "foo",
+              credentials: credentials,
+              encrypt_with_kms: encrypt_with_kms
+            }
+          end
+
+          context "to true as a boolean" do
+            let(:encrypt_with_kms) { true }
+
+            it "defaults encrypt_with_kms to true" do
+              expect(bucket.encrypt_with_kms).to be true
+            end
+
+            it "sets encryption_type to aws:kms" do
+              expect(bucket.encryption_type).to eq("aws:kms")
+            end
+          end
+
+          context "to true as a string" do
+            let(:encrypt_with_kms) { "true" }
+
+            it "defaults encrypt_with_kms to true" do
+              expect(bucket.encrypt_with_kms).to be true
+            end
+
+            it "sets encryption_type to aws:kms" do
+              expect(bucket.encryption_type).to eq("aws:kms")
+            end
+          end
+
+          context "to false as a boolean" do
+            let(:encrypt_with_kms) { false }
+
+            it "defaults encrypt_with_kms to false" do
+              expect(bucket.encrypt_with_kms).to be false
+            end
+
+            it "sets encryption_type to aws:kms" do
+              expect(bucket.encryption_type).to eq(:AES256)
+            end
+          end
+
+          context "to false as a string" do
+            let(:encrypt_with_kms) { "false" }
+
+            it "defaults encrypt_with_kms to false" do
+              expect(bucket.encrypt_with_kms).to be false
+            end
+
+            it "sets encryption_type to aws:kms" do
+              expect(bucket.encryption_type).to eq(:AES256)
+            end
+          end
+
+          context "to something not recognised" do
+            let(:encrypt_with_kms) { "bar" }
+
+            it "defaults encrypt_with_kms to false" do
+              expect(bucket.encrypt_with_kms).to be false
+            end
+
+            it "sets encryption_type to :AES256" do
+              expect(bucket.encryption_type).to eq(:AES256)
+            end
+          end
+        end
       end
 
       describe "#load" do
         let(:configs) do
           {
             name: "foo",
-            credentials: {
-              secret_access_key: "secret",
-              access_key_id: "access_key"
-            }
+            credentials: credentials
           }
         end
 
diff --git a/spec/lib/defra_ruby/aws/services/bucket_loader_service_spec.rb b/spec/lib/defra_ruby/aws/services/bucket_loader_service_spec.rb
index 92fce9c..8d0be07 100644
--- a/spec/lib/defra_ruby/aws/services/bucket_loader_service_spec.rb
+++ b/spec/lib/defra_ruby/aws/services/bucket_loader_service_spec.rb
@@ -5,31 +5,58 @@
 module DefraRuby
   module Aws
     RSpec.describe BucketLoaderService do
+
       describe "#run" do
-        let(:configs) do
-          {
-            credentials: {
-              access_key_id: "key_id",
-              secret_access_key: "secret"
-            },
-            name: "bulk"
-          }
-        end
+        let(:credentials) { { access_key_id: "key_id", secret_access_key: "secret" } }
         let(:bucket) { Bucket.new(configs) }
 
-        it "loads the given file to the s3 bucket" do
-          aws_resource = double(:aws_resource)
-          s3_bucket = double(:s3_bulk_bucket)
-          file = double(:file, path: "foo/bar/baz/test.csv")
-          s3_object = double(:s3_object)
-          result = double(:result)
+        context "when 'encrypt_with_kms' is not set" do
+          let(:configs) do
+            {
+              credentials: credentials,
+              name: "bulk"
+            }
+          end
+
+          it "loads the given file to the s3 bucket using :AES256" do
+            aws_resource = double(:aws_resource)
+            s3_bucket = double(:s3_bulk_bucket)
+            file = double(:file, path: "foo/bar/baz/test.csv")
+            s3_object = double(:s3_object)
+            result = double(:result)
+
+            expect(::Aws::S3::Resource).to receive(:new).and_return(aws_resource)
+            expect(aws_resource).to receive(:bucket).with("bulk").and_return(s3_bucket)
+            expect(s3_bucket).to receive(:object).with("test.csv").and_return(s3_object)
+            expect(s3_object).to receive(:upload_file).with("foo/bar/baz/test.csv", server_side_encryption: :AES256).and_return(result)
+
+            expect(described_class.run(bucket, file)).to be_a(Response)
+          end
+        end
+
+        context "when 'encrypt_with_kms' is set" do
+          let(:configs) do
+            {
+              credentials: credentials,
+              name: "bulk",
+              encrypt_with_kms: true
+            }
+          end
+
+          it "loads the given file to the s3 bucket using AWS:KMS" do
+            aws_resource = double(:aws_resource)
+            s3_bucket = double(:s3_bulk_bucket)
+            file = double(:file, path: "foo/bar/baz/test.csv")
+            s3_object = double(:s3_object)
+            result = double(:result)
 
-          expect(::Aws::S3::Resource).to receive(:new).and_return(aws_resource)
-          expect(aws_resource).to receive(:bucket).with("bulk").and_return(s3_bucket)
-          expect(s3_bucket).to receive(:object).with("test.csv").and_return(s3_object)
-          expect(s3_object).to receive(:upload_file).with("foo/bar/baz/test.csv", server_side_encryption: "aws:kms").and_return(result)
+            expect(::Aws::S3::Resource).to receive(:new).and_return(aws_resource)
+            expect(aws_resource).to receive(:bucket).with("bulk").and_return(s3_bucket)
+            expect(s3_bucket).to receive(:object).with("test.csv").and_return(s3_object)
+            expect(s3_object).to receive(:upload_file).with("foo/bar/baz/test.csv", server_side_encryption: "aws:kms").and_return(result)
 
-          expect(described_class.run(bucket, file)).to be_a(Response)
+            expect(described_class.run(bucket, file)).to be_a(Response)
+          end
         end
       end
     end