diff --git a/internal/services/cosmos/cosmosdb_mongo_collection_resource.go b/internal/services/cosmos/cosmosdb_mongo_collection_resource.go
index 850ba1700b85..e3c2f95ad3c7 100644
--- a/internal/services/cosmos/cosmosdb_mongo_collection_resource.go
+++ b/internal/services/cosmos/cosmosdb_mongo_collection_resource.go
@@ -79,9 +79,12 @@ func resourceCosmosDbMongoCollection() *pluginsdk.Resource {
 
 			// default TTL is simply an index on _ts with expireAfterOption, given we can't seem to set TTLs on a given index lets expose this to match the portal
 			"default_ttl_seconds": {
-				Type:         pluginsdk.TypeInt,
-				Optional:     true,
-				ValidateFunc: validation.IntAtLeast(-1),
+				Type:     pluginsdk.TypeInt,
+				Optional: true,
+				ValidateFunc: validation.All(
+					validation.IntAtLeast(-1),
+					validation.IntNotInSlice([]int{0}),
+				),
 			},
 
 			"analytical_storage_ttl": {
@@ -163,8 +166,8 @@ func resourceCosmosDbMongoCollectionCreate(d *pluginsdk.ResourceData, meta inter
 	}
 
 	var ttl *int
-	if v := d.Get("default_ttl_seconds").(int); v > 0 {
-		ttl = utils.Int(v)
+	if v, ok := d.GetOk("default_ttl_seconds"); ok {
+		ttl = utils.Int(v.(int))
 	}
 
 	indexes, hasIdKey := expandCosmosMongoCollectionIndex(d.Get("index").(*pluginsdk.Set).List(), ttl)
@@ -232,8 +235,8 @@ func resourceCosmosDbMongoCollectionUpdate(d *pluginsdk.ResourceData, meta inter
 	}
 
 	var ttl *int
-	if v := d.Get("default_ttl_seconds").(int); v > 0 {
-		ttl = utils.Int(v)
+	if v, ok := d.GetOk("default_ttl_seconds"); ok {
+		ttl = utils.Int(v.(int))
 	}
 
 	indexes, hasIdKey := expandCosmosMongoCollectionIndex(d.Get("index").(*pluginsdk.Set).List(), ttl)
diff --git a/internal/services/cosmos/cosmosdb_mongo_collection_resource_test.go b/internal/services/cosmos/cosmosdb_mongo_collection_resource_test.go
index 76ee7b9cc12c..e2d9a1bdd9f8 100644
--- a/internal/services/cosmos/cosmosdb_mongo_collection_resource_test.go
+++ b/internal/services/cosmos/cosmosdb_mongo_collection_resource_test.go
@@ -49,6 +49,21 @@ func TestAccCosmosDbMongoCollection_complete(t *testing.T) {
 	})
 }
 
+func TestAccCosmosDbMongoCollection_neverExpires(t *testing.T) {
+	data := acceptance.BuildTestData(t, "azurerm_cosmosdb_mongo_collection", "test")
+	r := CosmosMongoCollectionResource{}
+
+	data.ResourceTest(t, r, []acceptance.TestStep{
+		{
+			Config: r.neverExpires(data),
+			Check: acceptance.ComposeAggregateTestCheckFunc(
+				check.That(data.ResourceName).ExistsInAzure(r),
+			),
+		},
+		data.ImportStep(),
+	})
+}
+
 func TestAccCosmosDbMongoCollection_update(t *testing.T) {
 	data := acceptance.BuildTestData(t, "azurerm_cosmosdb_mongo_collection", "test")
 	r := CosmosMongoCollectionResource{}
@@ -463,3 +478,23 @@ resource "azurerm_cosmosdb_mongo_collection" "test" {
 }
 `, CosmosMongoDatabaseResource{}.basic(data), data.RandomInteger)
 }
+
+func (CosmosMongoCollectionResource) neverExpires(data acceptance.TestData) string {
+	return fmt.Sprintf(`
+%[1]s
+
+resource "azurerm_cosmosdb_mongo_collection" "test" {
+  name                = "acctest-%[2]d"
+  resource_group_name = azurerm_cosmosdb_mongo_database.test.resource_group_name
+  account_name        = azurerm_cosmosdb_mongo_database.test.account_name
+  database_name       = azurerm_cosmosdb_mongo_database.test.name
+
+  index {
+    keys   = ["_id"]
+    unique = true
+  }
+
+  default_ttl_seconds = -1
+}
+`, CosmosMongoDatabaseResource{}.basic(data), data.RandomInteger)
+}
diff --git a/website/docs/r/cosmosdb_mongo_collection.html.markdown b/website/docs/r/cosmosdb_mongo_collection.html.markdown
index 725c4b9f1016..35b2299b7243 100644
--- a/website/docs/r/cosmosdb_mongo_collection.html.markdown
+++ b/website/docs/r/cosmosdb_mongo_collection.html.markdown
@@ -48,9 +48,9 @@ The following arguments are supported:
 * `name` - (Required) Specifies the name of the Cosmos DB Mongo Collection. Changing this forces a new resource to be created.
 * `resource_group_name` - (Required) The name of the resource group in which the Cosmos DB Mongo Collection is created. Changing this forces a new resource to be created.
 * `database_name` - (Required) The name of the Cosmos DB Mongo Database in which the Cosmos DB Mongo Collection is created. Changing this forces a new resource to be created.
-* `default_ttl_seconds` - (Required) The default Time To Live in seconds. If the value is `-1` or `0`, items are not automatically expired.
 * `shard_key` - (Required) The name of the key to partition on for sharding. There must not be any other unique index keys.
 * `analytical_storage_ttl` - (Optional) The default time to live of Analytical Storage for this Mongo Collection. If present and the value is set to `-1`, it is equal to infinity, and items don’t expire by default. If present and the value is set to some number `n` – items will expire `n` seconds after their last modified time.
+* `default_ttl_seconds` - (Optional) The default Time To Live in seconds. If the value is `-1`, items are not automatically expired.
 * # `index` - (Optional) One or more `index` blocks as defined below.
 * `throughput` - (Optional) The throughput of the MongoDB collection (RU/s). Must be set in increments of `100`. The minimum value is `400`. This must be set upon database creation otherwise it cannot be updated without a manual terraform destroy-apply.
 * `autoscale_settings` - (Optional) An `autoscale_settings` block as defined below. This must be set upon database creation otherwise it cannot be updated without a manual terraform destroy-apply.