diff --git a/.changesets/format-date-and-time-objects-in-a-human-friendly-way.md b/.changesets/format-date-and-time-objects-in-a-human-friendly-way.md
new file mode 100644
index 000000000..97ac8dbad
--- /dev/null
+++ b/.changesets/format-date-and-time-objects-in-a-human-friendly-way.md
@@ -0,0 +1,6 @@
+---
+bump: patch
+type: change
+---
+
+Format the Date and Time objects in a human-friendly way. Previously, dates and times stored in sample data, like session data, would be shown as `#<Date>` and `#<Time>`. Now they will show as `#<Date: 2024-09-11>` and `#<Time: Time: 2024-09-12T13:14:15+02:00>` (UTC offset may be different for your time objects depending on the server setting).
diff --git a/lib/appsignal/utils/hash_sanitizer.rb b/lib/appsignal/utils/hash_sanitizer.rb
index 4d04f5af4..d7a1358d4 100644
--- a/lib/appsignal/utils/hash_sanitizer.rb
+++ b/lib/appsignal/utils/hash_sanitizer.rb
@@ -21,6 +21,10 @@ def sanitize_value(value, filter_keys, seen)
             sanitize_array(value, filter_keys, seen)
           when TrueClass, FalseClass, NilClass, Integer, String, Symbol, Float
             unmodified(value)
+          when Time
+            "#<Time: #{value.iso8601}>"
+          when Date
+            "#<Date: #{value.iso8601}>"
           else
             inspected(value)
           end
diff --git a/spec/lib/appsignal/transaction_spec.rb b/spec/lib/appsignal/transaction_spec.rb
index e6b492bca..0e31c60b7 100644
--- a/spec/lib/appsignal/transaction_spec.rb
+++ b/spec/lib/appsignal/transaction_spec.rb
@@ -797,6 +797,17 @@
       expect(transaction).to include_session_data(block_data)
     end
 
+    it "adds certain Ruby objects as Strings" do
+      transaction.add_session_data("time" => Time.utc(2024, 9, 12, 13, 14, 15))
+      transaction.add_session_data("date" => Date.new(2024, 9, 11))
+
+      transaction._sample
+      expect(transaction).to include_session_data(
+        "time" => "#<Time: 2024-09-12T13:14:15Z>",
+        "date" => "#<Date: 2024-09-11>"
+      )
+    end
+
     it "logs an error if an error occurred storing the session data" do
       transaction.add_session_data { raise "uh oh" }
 
diff --git a/spec/lib/appsignal/utils/hash_sanitizer_spec.rb b/spec/lib/appsignal/utils/hash_sanitizer_spec.rb
index 4d862739f..20beae524 100644
--- a/spec/lib/appsignal/utils/hash_sanitizer_spec.rb
+++ b/spec/lib/appsignal/utils/hash_sanitizer_spec.rb
@@ -10,6 +10,7 @@
       :float => 0.0,
       :bool_true => true,
       :bool_false => false,
+      :date => Date.new(2024, 9, 11),
       # Non-recursive appearances of the same array instance
       :some_arrays => [some_array, some_array],
       # Non-recursive appearances of the same hash instance
@@ -57,12 +58,12 @@
       expect(subject[:float]).to eq(0.0)
       expect(subject[:bool_true]).to be(true)
       expect(subject[:bool_false]).to be(false)
+      expect(subject[:date]).to eq("#<Date: 2024-09-11>")
       expect(subject[:nil]).to be_nil
       expect(subject[:int]).to eq(1)
       expect(subject[:int64]).to eq(1 << 64)
       expect(subject[:some_arrays]).to eq([[1, 2, 3], [1, 2, 3]])
-      expect(subject[:some_hashes]).to eq({ :a => { :a => 1, :b => 2 },
-:b => { :a => 1, :b => 2 } })
+      expect(subject[:some_hashes]).to eq(:a => { :a => 1, :b => 2 }, :b => { :a => 1, :b => 2 })
     end
 
     it "does not change the original params" do
@@ -71,6 +72,19 @@
       expect(params[:hash][:nested_array][2]).to eq(file)
     end
 
+    describe "time objects" do
+      it "returns a hash with normalized Time objects" do
+        args = {
+          :time_in_utc => Time.utc(2024, 9, 12, 13, 14, 15),
+          :time_with_timezone => Time.new(2024, 9, 12, 13, 14, 15, "+0900")
+        }
+        expect(described_class.sanitize(args)).to eq(
+          :time_in_utc => "#<Time: 2024-09-12T13:14:15Z>",
+          :time_with_timezone => "#<Time: 2024-09-12T13:14:15+09:00>"
+        )
+      end
+    end
+
     describe ":hash key" do
       subject { sanitized_params[:hash] }