diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9e95e301..955ca769 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -59,6 +59,7 @@ jobs:
           - "3.12"
           - "3.13"
           - "3.14"
+          - "3.14t"
           - "pypy-3.10"
           - "pypy-3.11"
         os: ["ubuntu-latest"]
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 9f430fa1..0cd0f65c 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -21,6 +21,8 @@ version 1.8.0-dev
 + Include test packages in the source distribution, so source distribution
   installations can be verified.
 + Fix an issue where some tests failed because they ignored PYTHONPATH.
++ Enable support for free-threading and build free-threaded wheels for
+  CPython 3.14. Thanks to @lysnikolaou and @ngoldbaum.
 
 version 1.7.2
 -----------------
diff --git a/src/isal/_isalmodule.c b/src/isal/_isalmodule.c
index a429d3a7..55f43917 100644
--- a/src/isal/_isalmodule.c
+++ b/src/isal/_isalmodule.c
@@ -31,6 +31,11 @@ PyInit__isal(void)
     if (m == NULL) {
         return NULL;
     }
+
+#ifdef Py_GIL_DISABLED
+    PyUnstable_Module_SetGIL(m, Py_MOD_GIL_NOT_USED);
+#endif
+
     PyModule_AddIntMacro(m, ISAL_MAJOR_VERSION);
     PyModule_AddIntMacro(m, ISAL_MINOR_VERSION);
     PyModule_AddIntMacro(m, ISAL_PATCH_VERSION);
diff --git a/src/isal/igzip_libmodule.c b/src/isal/igzip_libmodule.c
index de94ab01..d498145f 100644
--- a/src/isal/igzip_libmodule.c
+++ b/src/isal/igzip_libmodule.c
@@ -617,6 +617,11 @@ PyInit_igzip_lib(void)
     if (m == NULL)
         return NULL;
 
+#ifdef Py_GIL_DISABLED
+    PyUnstable_Module_SetGIL(m, Py_MOD_GIL_NOT_USED);
+#endif
+
+
     IsalError = PyErr_NewException("igzip_lib.IsalError", NULL, NULL);
     if (IsalError == NULL) {
         return NULL;
diff --git a/src/isal/isal_zlibmodule.c b/src/isal/isal_zlibmodule.c
index 67547be9..3a280ec8 100644
--- a/src/isal/isal_zlibmodule.c
+++ b/src/isal/isal_zlibmodule.c
@@ -2183,6 +2183,10 @@ PyInit_isal_zlib(void)
         return NULL;
     }
 
+#ifdef Py_GIL_DISABLED
+    PyUnstable_Module_SetGIL(m, Py_MOD_GIL_NOT_USED);
+#endif
+
     PyObject *igzip_lib_module = PyImport_ImportModule("isal.igzip_lib");
     if (igzip_lib_module == NULL) {
         return NULL;
diff --git a/tests/test_freethreading.py b/tests/test_freethreading.py
new file mode 100644
index 00000000..10d1d53b
--- /dev/null
+++ b/tests/test_freethreading.py
@@ -0,0 +1,110 @@
+import concurrent.futures
+import random
+import string
+import threading
+
+from isal import igzip_lib, isal_zlib
+
+import pytest
+
+
+HAMLET_SCENE = b"""
+LAERTES
+
+       O, fear me not.
+       I stay too long: but here my father comes.
+
+       Enter POLONIUS
+
+       A double blessing is a double grace,
+       Occasion smiles upon a second leave.
+
+LORD POLONIUS
+
+       Yet here, Laertes! aboard, aboard, for shame!
+       The wind sits in the shoulder of your sail,
+       And you are stay'd for. There; my blessing with thee!
+       And these few precepts in thy memory
+       See thou character. Give thy thoughts no tongue,
+       Nor any unproportioned thought his act.
+       Be thou familiar, but by no means vulgar.
+       Those friends thou hast, and their adoption tried,
+       Grapple them to thy soul with hoops of steel;
+       But do not dull thy palm with entertainment
+       Of each new-hatch'd, unfledged comrade. Beware
+       Of entrance to a quarrel, but being in,
+       Bear't that the opposed may beware of thee.
+       Give every man thy ear, but few thy voice;
+       Take each man's censure, but reserve thy judgment.
+       Costly thy habit as thy purse can buy,
+       But not express'd in fancy; rich, not gaudy;
+       For the apparel oft proclaims the man,
+       And they in France of the best rank and station
+       Are of a most select and generous chief in that.
+       Neither a borrower nor a lender be;
+       For loan oft loses both itself and friend,
+       And borrowing dulls the edge of husbandry.
+       This above all: to thine ownself be true,
+       And it must follow, as the night the day,
+       Thou canst not then be false to any man.
+       Farewell: my blessing season this in thee!
+
+LAERTES
+
+       Most humbly do I take my leave, my lord.
+
+LORD POLONIUS
+
+       The time invites you; go; your servants tend.
+
+LAERTES
+
+       Farewell, Ophelia; and remember well
+       What I have said to you.
+
+OPHELIA
+
+       'Tis in my memory lock'd,
+       And you yourself shall keep the key of it.
+
+LAERTES
+
+       Farewell.
+"""
+
+NUM_THREADS = 10
+NUM_ITERATIONS = 20
+NUM_JOBS = 50  # To simulate 50 jobs running in 10 threads
+barrier = threading.Barrier(parties=NUM_THREADS)
+
+
+def isal_compress_decompress(compress, decompress):
+    for _ in range(NUM_ITERATIONS):
+        barrier.wait()
+        x = compress(HAMLET_SCENE)
+        assert decompress(x) == HAMLET_SCENE
+
+        length = len(HAMLET_SCENE)
+        hamlet_random = HAMLET_SCENE + b"".join(
+            [s.encode() for s in random.choices(string.printable, k=length)]
+        )
+        barrier.wait()
+        x = compress(hamlet_random)
+        assert decompress(x) == hamlet_random
+
+
+@pytest.mark.parametrize(
+    "compress,decompress",
+    [
+        pytest.param(isal_zlib.compress, isal_zlib.decompress, id="zlib"),
+        pytest.param(igzip_lib.compress, igzip_lib.decompress, id="igzip"),
+    ]
+)
+def test_isal_compress_decompress_threaded(compress, decompress):
+    with concurrent.futures.ThreadPoolExecutor(NUM_THREADS) as executor:
+        futures = [
+            executor.submit(isal_compress_decompress, compress, decompress)
+            for _ in range(NUM_JOBS)
+        ]
+        for future in concurrent.futures.as_completed(futures):
+            future.result()  # To fire assertion error if there is one