diff --git a/Sources/Datadog/Tracing/UUIDs/TracingUUID.swift b/Sources/Datadog/Tracing/UUIDs/TracingUUID.swift
index 7cead494b4..947482273a 100644
--- a/Sources/Datadog/Tracing/UUIDs/TracingUUID.swift
+++ b/Sources/Datadog/Tracing/UUIDs/TracingUUID.swift
@@ -40,9 +40,9 @@ internal struct TracingUUID: Equatable, Hashable {
         case .hexadecimal:
             return String(rawValue, radix: 16)
         case .hexadecimal16Chars:
-            return String(format: "%016x", rawValue)
+            return String(format: "%016llx", rawValue)
         case .hexadecimal32Chars:
-            return String(format: "%032x", rawValue)
+            return String(format: "%032llx", rawValue)
         }
     }
 }
diff --git a/Tests/DatadogTests/Datadog/Tracing/UUIDs/TracingUUIDTests.swift b/Tests/DatadogTests/Datadog/Tracing/UUIDs/TracingUUIDTests.swift
index 85ed3e5651..41589e803b 100644
--- a/Tests/DatadogTests/Datadog/Tracing/UUIDs/TracingUUIDTests.swift
+++ b/Tests/DatadogTests/Datadog/Tracing/UUIDs/TracingUUIDTests.swift
@@ -18,6 +18,26 @@ class UUIDTests: XCTestCase {
         XCTAssertEqual(TracingUUID(rawValue: .max).toString(.hexadecimal), "ffffffffffffffff")
     }
 
+    func testTo16CharHexadecimalStringConversion() {
+        XCTAssertEqual(TracingUUID(rawValue: 0).toString(.hexadecimal16Chars), "0000000000000000")
+        XCTAssertEqual(TracingUUID(rawValue: 1).toString(.hexadecimal16Chars), "0000000000000001")
+        XCTAssertEqual(TracingUUID(rawValue: 15).toString(.hexadecimal16Chars), "000000000000000f")
+        XCTAssertEqual(TracingUUID(rawValue: 16).toString(.hexadecimal16Chars), "0000000000000010")
+        XCTAssertEqual(TracingUUID(rawValue: 123).toString(.hexadecimal16Chars), "000000000000007b")
+        XCTAssertEqual(TracingUUID(rawValue: 123_456).toString(.hexadecimal16Chars), "000000000001e240")
+        XCTAssertEqual(TracingUUID(rawValue: .max).toString(.hexadecimal16Chars), "ffffffffffffffff")
+    }
+
+    func testTo32CharHexadecimalStringConversion() {
+        XCTAssertEqual(TracingUUID(rawValue: 0).toString(.hexadecimal32Chars), "00000000000000000000000000000000")
+        XCTAssertEqual(TracingUUID(rawValue: 1).toString(.hexadecimal32Chars), "00000000000000000000000000000001")
+        XCTAssertEqual(TracingUUID(rawValue: 15).toString(.hexadecimal32Chars), "0000000000000000000000000000000f")
+        XCTAssertEqual(TracingUUID(rawValue: 16).toString(.hexadecimal32Chars), "00000000000000000000000000000010")
+        XCTAssertEqual(TracingUUID(rawValue: 123).toString(.hexadecimal32Chars), "0000000000000000000000000000007b")
+        XCTAssertEqual(TracingUUID(rawValue: 123_456).toString(.hexadecimal32Chars), "0000000000000000000000000001e240")
+        XCTAssertEqual(TracingUUID(rawValue: .max).toString(.hexadecimal32Chars), "0000000000000000ffffffffffffffff")
+    }
+
     func testToDecimalStringConversion() {
         XCTAssertEqual(TracingUUID(rawValue: 0).toString(.decimal), "0")
         XCTAssertEqual(TracingUUID(rawValue: 1).toString(.decimal), "1")