diff --git a/changelogs/fragments/606-ec2_vol-set-iops-even-if-unchanged-for-boto-req.yml b/changelogs/fragments/606-ec2_vol-set-iops-even-if-unchanged-for-boto-req.yml
new file mode 100644
index 00000000000..c3c1580d463
--- /dev/null
+++ b/changelogs/fragments/606-ec2_vol-set-iops-even-if-unchanged-for-boto-req.yml
@@ -0,0 +1,5 @@
+bugfixes:
+- >-
+  ec2_vol - Sets the Iops value in req_obj even if the iops value
+  has not changed, to allow modifying volume types that require
+  passing an iops value to boto. (https://github.com/ansible-collections/amazon.aws/pull/606)
diff --git a/plugins/modules/ec2_vol.py b/plugins/modules/ec2_vol.py
index a7b7990c916..ffbc94f176f 100644
--- a/plugins/modules/ec2_vol.py
+++ b/plugins/modules/ec2_vol.py
@@ -373,6 +373,8 @@ def update_volume(module, ec2_conn, volume):
             if target_iops != original_iops:
                 iops_changed = True
                 req_obj['Iops'] = target_iops
+            else:
+                req_obj['Iops'] = original_iops
         else:
             # If no IOPS value is specified and there was a volume_type update to gp3,
             # the existing value is retained, unless a volume type is modified that supports different values,
diff --git a/tests/integration/constraints.txt b/tests/integration/constraints.txt
new file mode 100644
index 00000000000..e69de29bb2d