diff --git a/Readme.md b/Readme.md
index 5a8eff34..d8d137fb 100644
--- a/Readme.md
+++ b/Readme.md
@@ -70,6 +70,7 @@ functions:
 | Igbinary         | `${bref-extra:igbinary-php-81}`        |
 | Imagick          | `${bref-extra:imagick-php-81}`         |
 | IMAP             | `${bref-extra:imap-php-81}`            |
+| Iconv Extra      | `${bref-extra:iconv-extra-php-81}`     |
 | LDAP             | `${bref-extra:ldap-php-81}`            |
 | Mailparse        | `${bref-extra:mailparse-php-81}`       |
 | MaxMind DB       | `${bref-extra:maxminddb-php-81}`       |
@@ -105,6 +106,17 @@ functions:
 | xmlrpc           | `${bref-extra:xmlrpc-php-81}`          |
 | Yaml             | `${bref-extra:yaml-php-81}`            |
 
+### Iconv Extra setup
+
+The Iconv Extra layer provides additional glibc conversion modules for legacy character encodings,
+such as Windows-1250. Set `GCONV_PATH` in `serverless.yaml` so glibc can find the modules before PHP starts:
+
+```yaml
+provider:
+    environment:
+        GCONV_PATH: /opt/lib/gconv
+```
+
 ### Blackfire installation
 
 The Blackfire layer only have the probe installed.
diff --git a/layers/iconv-extra/Dockerfile b/layers/iconv-extra/Dockerfile
new file mode 100644
index 00000000..64c5d376
--- /dev/null
+++ b/layers/iconv-extra/Dockerfile
@@ -0,0 +1,8 @@
+ARG PHP_VERSION
+ARG BREF_VERSION
+
+FROM bref/build-php-$PHP_VERSION:$BREF_VERSION AS ext
+
+FROM scratch
+
+COPY --from=ext /usr/lib64/gconv/ /opt/lib/gconv/
diff --git a/layers/iconv-extra/config.json b/layers/iconv-extra/config.json
new file mode 100644
index 00000000..205ba218
--- /dev/null
+++ b/layers/iconv-extra/config.json
@@ -0,0 +1,8 @@
+{
+    "php": [
+        "82",
+        "83",
+        "84",
+        "85"
+    ]
+}
diff --git a/layers/iconv-extra/test.php b/layers/iconv-extra/test.php
new file mode 100644
index 00000000..3980ebc5
--- /dev/null
+++ b/layers/iconv-extra/test.php
@@ -0,0 +1,11 @@
+<?php
+
+$input = hex2bin('f5fbc1c9');
+$result = iconv('WINDOWS-1250', 'UTF-8', $input);
+
+if ($result !== 'őűÁÉ') {
+    echo 'FAIL: WINDOWS-1250 conversion is unavailable.', PHP_EOL;
+    exit(1);
+}
+
+exit(0);
diff --git a/tests/Dockerfile b/tests/Dockerfile
index 792678cc..720076ea 100644
--- a/tests/Dockerfile
+++ b/tests/Dockerfile
@@ -6,3 +6,4 @@ FROM bref/php-$PHP_VERSION:3
 
 COPY --from=ext /opt /opt
 ENV ODBCSYSINI=/opt/microsoft/conf/
+ENV GCONV_PATH=/opt/lib/gconv