diff --git a/codebuild/spec/buildspec_openssl3fips.yml b/codebuild/spec/buildspec_openssl3fips.yml
new file mode 100644
index 00000000000..4ede818eb32
--- /dev/null
+++ b/codebuild/spec/buildspec_openssl3fips.yml
@@ -0,0 +1,34 @@
+---
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"). You may not use
+# this file except in compliance with the License. A copy of the License is
+# located at
+#
+# http://aws.amazon.com/apache2.0/
+#
+# or in the "license" file accompanying this file. This file is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied. See the License for the specific language governing permissions and
+# limitations under the License.
+
+version: 0.2
+      
+phases:
+  build:
+    on-failure: ABORT
+    commands:
+      - |
+        cmake . -Bbuild \
+          -DCMAKE_PREFIX_PATH=/usr/local/openssl-3.0-fips \
+          -DCMAKE_BUILD_TYPE=RelWithDebInfo \
+          -DASAN=ON \
+          -DUBSAN=ON
+      - cmake --build ./build -- -j $(nproc)
+  post_build:
+    on-failure: ABORT
+    commands:
+      - export CTEST_OUTPUT_ON_FAILURE=1
+      - export CTEST_PARALLEL_LEVEL=$(nproc)
+      # openssl3fips is still a work-in-progress. Not all tests pass.
+      - make -C build test -- ARGS="-R 's2n_build_test|s2n_fips_test'"
diff --git a/crypto/s2n_fips.c b/crypto/s2n_fips.c
index b38a4d86ffd..85b03ca955e 100644
--- a/crypto/s2n_fips.c
+++ b/crypto/s2n_fips.c
@@ -45,6 +45,8 @@ bool s2n_libcrypto_is_fips(void)
     if (FIPS_mode() == 1) {
         return true;
     }
+#elif S2N_OPENSSL_VERSION_AT_LEAST(3, 0, 0)
+    return EVP_default_properties_is_fips_enabled(NULL);
 #endif
     return false;
 }
@@ -52,9 +54,22 @@ bool s2n_libcrypto_is_fips(void)
 int s2n_fips_init(void)
 {
     s2n_fips_mode_enabled = s2n_libcrypto_is_fips();
-#if defined(OPENSSL_FIPS)
+
+    /* When using Openssl, ONLY 3.0 currently supports FIPS.
+     * openssl-1.0.2-fips is no longer supported.
+     * openssl > 3.0 will likely have a FIPS 140-3 certificate instead of a
+     * FIPS 140-2 certificate, which will require additional review in order
+     * to properly integrate.
+     */
+#if defined(OPENSSL_FIPS) || S2N_OPENSSL_VERSION_AT_LEAST(3, 1, 0)
     POSIX_ENSURE(!s2n_fips_mode_enabled, S2N_ERR_FIPS_MODE_UNSUPPORTED);
 #endif
+
+    /* For now, openssl is only supported for testing */
+    if (s2n_libcrypto_is_openssl_fips()) {
+        POSIX_ENSURE(s2n_in_unit_test(), S2N_ERR_FIPS_MODE_UNSUPPORTED);
+    }
+
     return S2N_SUCCESS;
 }
 
diff --git a/crypto/s2n_libcrypto.c b/crypto/s2n_libcrypto.c
index a3172dc5d93..3497af60881 100644
--- a/crypto/s2n_libcrypto.c
+++ b/crypto/s2n_libcrypto.c
@@ -125,6 +125,11 @@ bool s2n_libcrypto_is_openssl(void)
     return !is_other_libcrypto_variant;
 }
 
+bool s2n_libcrypto_is_openssl_fips(void)
+{
+    return s2n_libcrypto_is_openssl() && s2n_is_in_fips_mode();
+}
+
 bool s2n_libcrypto_is_awslc()
 {
 #if defined(OPENSSL_IS_AWSLC)
@@ -134,6 +139,11 @@ bool s2n_libcrypto_is_awslc()
 #endif
 }
 
+bool s2n_libcrypto_is_awslc_fips(void)
+{
+    return s2n_libcrypto_is_awslc() && s2n_is_in_fips_mode();
+}
+
 uint64_t s2n_libcrypto_awslc_api_version(void)
 {
 #if defined(OPENSSL_IS_AWSLC)
diff --git a/crypto/s2n_openssl.h b/crypto/s2n_openssl.h
index eaee87700c3..cd2763a8fe2 100644
--- a/crypto/s2n_openssl.h
+++ b/crypto/s2n_openssl.h
@@ -51,6 +51,8 @@
 #endif
 
 bool s2n_libcrypto_is_openssl(void);
+bool s2n_libcrypto_is_openssl_fips(void);
 bool s2n_libcrypto_is_awslc();
+bool s2n_libcrypto_is_awslc_fips(void);
 bool s2n_libcrypto_is_boringssl();
 bool s2n_libcrypto_is_libressl();
diff --git a/tests/unit/s2n_build_test.c b/tests/unit/s2n_build_test.c
index 6bab8a80e99..7c161e7b4dd 100644
--- a/tests/unit/s2n_build_test.c
+++ b/tests/unit/s2n_build_test.c
@@ -73,6 +73,7 @@ S2N_RESULT s2n_check_supported_libcrypto(const char *s2n_libcrypto)
     const struct {
         const char *libcrypto;
         bool is_openssl;
+        bool is_opensslfips;
     } supported_libcrypto[] = {
         { .libcrypto = "awslc", .is_openssl = false },
         { .libcrypto = "awslc-fips", .is_openssl = false },
@@ -83,24 +84,24 @@ S2N_RESULT s2n_check_supported_libcrypto(const char *s2n_libcrypto)
         { .libcrypto = "openssl-1.0.2-fips", .is_openssl = true },
         { .libcrypto = "openssl-1.1.1", .is_openssl = true },
         { .libcrypto = "openssl-3.0", .is_openssl = true },
+        { .libcrypto = "openssl-3.0-fips", .is_openssl = true, .is_opensslfips = true },
         { .libcrypto = "openssl-3.4", .is_openssl = true },
     };
 
     for (size_t i = 0; i < s2n_array_len(supported_libcrypto); i++) {
-        /* The linked libcryto is one of the known supported libcrypto variants */
-        if (strcmp(s2n_libcrypto, supported_libcrypto[i].libcrypto) == 0) {
-            if (supported_libcrypto[i].is_openssl) {
-                EXPECT_TRUE(s2n_libcrypto_is_openssl());
-            } else {
-                EXPECT_FALSE(s2n_libcrypto_is_openssl());
-            }
-
-            return S2N_RESULT_OK;
+        if (strcmp(s2n_libcrypto, supported_libcrypto[i].libcrypto) != 0) {
+            continue;
         }
+        EXPECT_EQUAL(s2n_libcrypto_is_openssl(), supported_libcrypto[i].is_openssl);
+        EXPECT_EQUAL(s2n_libcrypto_is_openssl_fips(), supported_libcrypto[i].is_opensslfips);
+        return S2N_RESULT_OK;
     }
 
-    /* Testing with an unexpected libcrypto. */
-    return S2N_RESULT_ERROR;
+    /* Fail if no matching libcrypto was found.
+     * Since we check for openssl via process of elimination, we must know
+     * and test the full list of non-openssl libcryptos.
+     */
+    FAIL_MSG("Unknown libcrypto - update supported_libcrypto list");
 }
 
 int main()
@@ -128,16 +129,13 @@ int main()
         END_TEST();
     }
 
-    /* Ensure that FIPS mode is enabled when linked to AWS-LC-FIPS, and disabled when linked to AWS-LC */
-    if (strstr(s2n_libcrypto, "awslc") != NULL) {
-        s2n_fips_mode fips_mode = S2N_FIPS_MODE_DISABLED;
-        EXPECT_SUCCESS(s2n_get_fips_mode(&fips_mode));
-
-        if (strstr(s2n_libcrypto, "fips") != NULL) {
-            EXPECT_EQUAL(fips_mode, S2N_FIPS_MODE_ENABLED);
-        } else {
-            EXPECT_EQUAL(fips_mode, S2N_FIPS_MODE_DISABLED);
-        }
+    /* Ensure that FIPS mode is enabled only when linked to a fips library */
+    s2n_fips_mode fips_mode = S2N_FIPS_MODE_DISABLED;
+    EXPECT_SUCCESS(s2n_get_fips_mode(&fips_mode));
+    if (strstr(s2n_libcrypto, "fips") && !strstr(s2n_libcrypto, "1.0.2")) {
+        EXPECT_EQUAL(fips_mode, S2N_FIPS_MODE_ENABLED);
+    } else {
+        EXPECT_EQUAL(fips_mode, S2N_FIPS_MODE_DISABLED);
     }
 
     char s2n_libcrypto_copy[MAX_LIBCRYPTO_NAME_LEN] = { 0 };
@@ -151,7 +149,8 @@ int main()
     {
         if (strstr(name, "awslc") != NULL) {
             /* Early versions of awslc's SSLeay_version return an inaccurate value left over
-	     * after its fork from BoringSSL.  */
+             * after its fork from BoringSSL.
+             */
             EXPECT_TRUE(s2n_libcrypto_is_awslc());
         } else {
             /* Any other library should have the name of the library (modulo case) in its version string.  */
diff --git a/tests/unit/s2n_fips_test.c b/tests/unit/s2n_fips_test.c
index c4e5bdc134e..31274231d1b 100644
--- a/tests/unit/s2n_fips_test.c
+++ b/tests/unit/s2n_fips_test.c
@@ -49,5 +49,20 @@ int main()
         }
     }
 
+    /* Test: FIPS mode not currently supported for openssl outside of tests. */
+    if (s2n_libcrypto_is_openssl_fips()) {
+        /* s2n_fips_init was already called by BEGIN_TEST.
+         * Call it again to confirm that we are allowed to call it repeatedly.
+         */
+        EXPECT_SUCCESS(s2n_fips_init());
+
+        EXPECT_SUCCESS(s2n_in_unit_test_set(false));
+        EXPECT_FAILURE_WITH_ERRNO(s2n_fips_init(), S2N_ERR_FIPS_MODE_UNSUPPORTED);
+        EXPECT_SUCCESS(s2n_in_unit_test_set(true));
+
+        /* Make sure s2n_fips_init still works */
+        EXPECT_SUCCESS(s2n_fips_init());
+    }
+
     END_TEST();
 }