diff --git a/.changelog/24005.txt b/.changelog/24005.txt
new file mode 100644
index 000000000000..07a3e4a8da81
--- /dev/null
+++ b/.changelog/24005.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+resource/aws_ecs_capacity_provider: Allow an `instance_warmup_period` of `0` in the `managed_scaling` configuration block
+```
\ No newline at end of file
diff --git a/internal/service/ecs/capacity_provider.go b/internal/service/ecs/capacity_provider.go
index f0945d968dfa..72b869ef4b28 100644
--- a/internal/service/ecs/capacity_provider.go
+++ b/internal/service/ecs/capacity_provider.go
@@ -58,7 +58,7 @@ func ResourceCapacityProvider() *schema.Resource {
 										Type:         schema.TypeInt,
 										Optional:     true,
 										Computed:     true,
-										ValidateFunc: validation.IntBetween(1, 10000),
+										ValidateFunc: validation.IntBetween(0, 10000),
 									},
 									"maximum_scaling_step_size": {
 										Type:         schema.TypeInt,
@@ -345,7 +345,7 @@ func expandManagedScaling(configured interface{}) *ecs.ManagedScaling {
 
 	managedScaling := ecs.ManagedScaling{}
 
-	if val, ok := p["instance_warmup_period"].(int); ok && val != 0 {
+	if val, ok := p["instance_warmup_period"].(int); ok {
 		managedScaling.InstanceWarmupPeriod = aws.Int64(int64(val))
 	}
 	if val, ok := p["maximum_scaling_step_size"].(int); ok && val != 0 {
diff --git a/internal/service/ecs/capacity_provider_test.go b/internal/service/ecs/capacity_provider_test.go
index 083a76d99ea0..21e90742b223 100644
--- a/internal/service/ecs/capacity_provider_test.go
+++ b/internal/service/ecs/capacity_provider_test.go
@@ -304,19 +304,19 @@ resource "aws_autoscaling_group" "test" {
 }
 
 func testAccCapacityProviderConfig(rName string) string {
-	return testAccCapacityProviderBaseConfig(rName) + fmt.Sprintf(`
+	return acctest.ConfigCompose(testAccCapacityProviderBaseConfig(rName), fmt.Sprintf(`
 resource "aws_ecs_capacity_provider" "test" {
-  name = %q
+  name = %[1]q
 
   auto_scaling_group_provider {
     auto_scaling_group_arn = aws_autoscaling_group.test.arn
   }
 }
-`, rName)
+`, rName))
 }
 
 func testAccCapacityProviderManagedScalingConfig(rName, status string, warmup, max, min, cap int) string {
-	return testAccCapacityProviderBaseConfig(rName) + fmt.Sprintf(`
+	return acctest.ConfigCompose(testAccCapacityProviderBaseConfig(rName), fmt.Sprintf(`
 resource "aws_ecs_capacity_provider" "test" {
   name = %[1]q
 
@@ -332,11 +332,11 @@ resource "aws_ecs_capacity_provider" "test" {
     }
   }
 }
-`, rName, warmup, max, min, status, cap)
+`, rName, warmup, max, min, status, cap))
 }
 
 func testAccCapacityProviderManagedScalingPartialConfig(rName string) string {
-	return testAccCapacityProviderBaseConfig(rName) + fmt.Sprintf(`
+	return acctest.ConfigCompose(testAccCapacityProviderBaseConfig(rName), fmt.Sprintf(`
 resource "aws_ecs_capacity_provider" "test" {
   name = %[1]q
 
@@ -349,11 +349,11 @@ resource "aws_ecs_capacity_provider" "test" {
     }
   }
 }
-`, rName)
+`, rName))
 }
 
 func testAccCapacityProviderTags1Config(rName, tag1Key, tag1Value string) string {
-	return testAccCapacityProviderBaseConfig(rName) + fmt.Sprintf(`
+	return acctest.ConfigCompose(testAccCapacityProviderBaseConfig(rName), fmt.Sprintf(`
 resource "aws_ecs_capacity_provider" "test" {
   name = %[1]q
 
@@ -365,11 +365,11 @@ resource "aws_ecs_capacity_provider" "test" {
     auto_scaling_group_arn = aws_autoscaling_group.test.arn
   }
 }
-`, rName, tag1Key, tag1Value)
+`, rName, tag1Key, tag1Value))
 }
 
 func testAccCapacityProviderTags2Config(rName, tag1Key, tag1Value, tag2Key, tag2Value string) string {
-	return testAccCapacityProviderBaseConfig(rName) + fmt.Sprintf(`
+	return acctest.ConfigCompose(testAccCapacityProviderBaseConfig(rName), fmt.Sprintf(`
 resource "aws_ecs_capacity_provider" "test" {
   name = %[1]q
 
@@ -382,5 +382,5 @@ resource "aws_ecs_capacity_provider" "test" {
     auto_scaling_group_arn = aws_autoscaling_group.test.arn
   }
 }
-`, rName, tag1Key, tag1Value, tag2Key, tag2Value)
+`, rName, tag1Key, tag1Value, tag2Key, tag2Value))
 }