diff --git a/shard.yml b/shard.yml
index 674d7b3..e573f96 100644
--- a/shard.yml
+++ b/shard.yml
@@ -11,7 +11,7 @@ license: MIT
 dependencies:
   carbon:
     github: luckyframework/carbon
-    version: ~> 0.4.0
+    version: ~> 0.5.1
   habitat:
     github: luckyframework/habitat
     version: ~> 0.4.8
diff --git a/spec/carbon_sendgrid_adapter_spec.cr b/spec/carbon_sendgrid_adapter_spec.cr
index e9c9372..68a82c4 100644
--- a/spec/carbon_sendgrid_adapter_spec.cr
+++ b/spec/carbon_sendgrid_adapter_spec.cr
@@ -154,6 +154,15 @@ describe Carbon::SendGridAdapter do
 
       params["personalizations"].as(Array).first.has_key?("asm").should eq(false)
     end
+
+    it "handles attachments" do
+      email = FakeEmail.new(text_body: "0")
+      params = Carbon::SendGridAdapter::Email.new(email, api_key: "fake_key").params
+      attachments = params["attachments"].as(Array)
+      attachments.size.should eq(1)
+      attachments.first["filename"].should eq("contract.pdf")
+      Base64.decode_string(attachments.first["content"].to_s).should eq("Sign here")
+    end
   end
 end
 
diff --git a/spec/support/fake_email.cr b/spec/support/fake_email.cr
index fab39f0..7b6e7ae 100644
--- a/spec/support/fake_email.cr
+++ b/spec/support/fake_email.cr
@@ -18,4 +18,13 @@ class FakeEmail < Carbon::Email
   cc @cc
   bcc @bcc
   subject @subject
+  attachment contract
+
+  def contract
+    {
+      io:        IO::Memory.new("Sign here"),
+      file_name: "contract.pdf",
+      mime_type: "application/pdf",
+    }
+  end
 end
diff --git a/src/carbon_sendgrid_adapter.cr b/src/carbon_sendgrid_adapter.cr
index 2fd9881..2485017 100644
--- a/src/carbon_sendgrid_adapter.cr
+++ b/src/carbon_sendgrid_adapter.cr
@@ -1,6 +1,7 @@
 require "http"
 require "json"
 require "carbon"
+require "base64"
 require "./errors"
 require "./carbon_sendgrid_extensions"
 
@@ -35,7 +36,6 @@ class Carbon::SendGridAdapter < Carbon::Adapter
     end
 
     # :nodoc:
-    # Used only for testing
     def params
       data = {
         "personalizations" => [personalizations],
@@ -45,6 +45,7 @@ class Carbon::SendGridAdapter < Carbon::Adapter
         "reply_to"         => reply_to_params,
         "asm"              => {"group_id" => 0, "groups_to_display" => [] of Int32},
         "mail_settings"    => {sandbox_mode: {enable: sandbox?}},
+        "attachments"      => attachments,
       }.compact
 
       if asm_data = email.asm
@@ -138,6 +139,19 @@ class Carbon::SendGridAdapter < Carbon::Adapter
       ].compact
     end
 
+    private def attachments : Array(Hash(String, String))
+      files = [] of Hash(String, String)
+      email.attachments.map do |attachment|
+        case attachment
+        in AttachFile, ResourceFile
+          files.push({"content" => Base64.encode(File.read(attachment[:file_path])), "type" => attachment[:mime_type].to_s, "filename" => attachment[:file_name].to_s, "disposition" => "attachment"})
+        in AttachIO, ResourceIO
+          files.push({"content" => Base64.encode(attachment[:io].to_s), "type" => attachment[:mime_type].to_s, "filename" => attachment[:file_name].to_s, "disposition" => "attachment"})
+        end
+      end
+      files
+    end
+
     private def text_content : Hash(String, String)?
       body = email.text_body
       if body && !body.empty?