diff --git a/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java b/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
index 1d5bfce1ee..2582c9399b 100644
--- a/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
+++ b/buffer/src/main/java/io/netty/buffer/ByteBufUtil.java
@@ -586,18 +586,13 @@ public final class ByteBufUtil {
                     buffer._setByte(writerIndex++, WRITE_UTF_UNKNOWN);
                     continue;
                 }
-                final char c2;
-                try {
-                    // Surrogate Pair consumes 2 characters. Optimistically try to get the next character to avoid
-                    // duplicate bounds checking with charAt. If an IndexOutOfBoundsException is thrown we will
-                    // re-throw a more informative exception describing the problem.
-                    c2 = seq.charAt(++i);
-                } catch (IndexOutOfBoundsException ignored) {
+                // Surrogate Pair consumes 2 characters.
+                if (++i == end) {
                     buffer._setByte(writerIndex++, WRITE_UTF_UNKNOWN);
                     break;
                 }
                 // Extra method to allow inlining the rest of writeUtf8 which is the most likely code path.
-                writerIndex = writeUtf8Surrogate(buffer, writerIndex, c, c2);
+                writerIndex = writeUtf8Surrogate(buffer, writerIndex, c, seq.charAt(i));
             } else {
                 buffer._setByte(writerIndex++, (byte) (0xe0 | (c >> 12)));
                 buffer._setByte(writerIndex++, (byte) (0x80 | ((c >> 6) & 0x3f)));
@@ -684,17 +679,13 @@ public final class ByteBufUtil {
                     // WRITE_UTF_UNKNOWN
                     continue;
                 }
-                final char c2;
-                try {
-                    // Surrogate Pair consumes 2 characters. Optimistically try to get the next character to avoid
-                    // duplicate bounds checking with charAt.
-                    c2 = seq.charAt(++i);
-                } catch (IndexOutOfBoundsException ignored) {
+                // Surrogate Pair consumes 2 characters.
+                if (++i == end) {
                     encodedLength++;
                     // WRITE_UTF_UNKNOWN
                     break;
                 }
-                if (!Character.isLowSurrogate(c2)) {
+                if (!Character.isLowSurrogate(seq.charAt(i))) {
                     // WRITE_UTF_UNKNOWN + (Character.isHighSurrogate(c2) ? WRITE_UTF_UNKNOWN : c2)
                     encodedLength += 2;
                     continue;
diff --git a/buffer/src/test/java/io/netty/buffer/ByteBufUtilTest.java b/buffer/src/test/java/io/netty/buffer/ByteBufUtilTest.java
index 8721be1c7a..78fa1a7344 100644
--- a/buffer/src/test/java/io/netty/buffer/ByteBufUtilTest.java
+++ b/buffer/src/test/java/io/netty/buffer/ByteBufUtilTest.java
@@ -524,6 +524,20 @@ public class ByteBufUtilTest {
         buf2.release();
     }
 
+    @Test
+    public void testWriteUtf8SubsequenceSplitSurrogate() {
+        String usAscii = "\uD800\uDC00"; // surrogate pair: one code point, two chars
+        ByteBuf buf = Unpooled.buffer(16);
+        buf.writeBytes(usAscii.substring(0, 1).getBytes(CharsetUtil.UTF_8));
+        ByteBuf buf2 = Unpooled.buffer(16);
+        ByteBufUtil.writeUtf8(buf2, usAscii, 0, 1);
+
+        assertEquals(buf, buf2);
+
+        buf.release();
+        buf2.release();
+    }
+
     @Test
     public void testReserveAndWriteUtf8Subsequence() {
         String usAscii = "Some UTF-8 like äÄ∏ŒŒ";