diff --git a/.github/workflows/ci-testing.yml b/.github/workflows/ci-testing.yml
index e9f7a8cb..729773cd 100644
--- a/.github/workflows/ci-testing.yml
+++ b/.github/workflows/ci-testing.yml
@@ -33,17 +33,9 @@ jobs:
       fail-fast: false
       matrix:
         netbox-version:
-          # - v4.0.0 has mandatory tenant group
-          - v4.0.1
-          - v4.0.2
-          - v4.0.3
-          # - v4.0.4 does not exist for some reason
-          - v4.0.5
-          - v4.0.6
-          - v4.0.7
-          - v4.0.8
-          - v4.0.9
-          - v4.0.10
+          - v4.1.0
+          - v4.1.1
+          - v4.1.2
     steps:
       - uses: actions/checkout@v4
       - name: Set up Go
diff --git a/GNUmakefile b/GNUmakefile
index 8b0e36cd..4db5ec4b 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -3,7 +3,7 @@ TEST_FUNC?=TestAccNetboxEventRule_basic
 GOFMT_FILES?=$$(find . -name '*.go' | grep -v vendor)
 DOCKER_COMPOSE=docker compose
 
-export NETBOX_VERSION=v4.0.10
+export NETBOX_VERSION=v4.1.2
 export NETBOX_SERVER_URL=http://localhost:8001
 export NETBOX_API_TOKEN=0123456789abcdef0123456789abcdef01234567
 export NETBOX_TOKEN=$(NETBOX_API_TOKEN)
diff --git a/README.md b/README.md
index 27489531..304aaa58 100644
--- a/README.md
+++ b/README.md
@@ -18,7 +18,8 @@ Since version [1.6.6](https://github.com/e-breuninger/terraform-provider-netbox/
 
 | Netbox version  | Provider version |
 | --------------- | ---------------- |
-| v4.0.0 - 4.0.10 | v3.9.0 and up    |
+| v4.1.0 - 4.1.2  | v3.10.0 and up   |
+| v4.0.0 - 4.0.10 | v3.9.0 - 3.9.1   |
 | v3.7.0 - 3.7.8  | v3.8.0 - 3.8.9   |
 | v3.6.0 - 3.6.9  | v3.7.0 - 3.7.7   |
 | v3.5.1 - 3.5.9  | v3.6.x           |
diff --git a/netbox/data_source_netbox_virtual_machines.go b/netbox/data_source_netbox_virtual_machines.go
index 7b84e84b..2180164d 100644
--- a/netbox/data_source_netbox_virtual_machines.go
+++ b/netbox/data_source_netbox_virtual_machines.go
@@ -244,7 +244,7 @@ func dataSourceNetboxVirtualMachineRead(d *schema.ResourceData, m interface{}) e
 			mapping["custom_fields"] = v.CustomFields
 		}
 		if v.Disk != nil {
-			mapping["disk_size_gb"] = *v.Disk
+			mapping["disk_size_gb"] = *v.Disk / 1000
 		}
 		if v.LocalContextData != nil {
 			if localContextData, err := json.Marshal(v.LocalContextData); err == nil {
diff --git a/netbox/provider.go b/netbox/provider.go
index 7e83144c..bd909cfe 100644
--- a/netbox/provider.go
+++ b/netbox/provider.go
@@ -295,7 +295,7 @@ func providerConfigure(ctx context.Context, data *schema.ResourceData) (interfac
 
 		netboxVersion := res.GetPayload().(map[string]interface{})["netbox-version"].(string)
 
-		supportedVersions := []string{"4.0.0", "4.0.1", "4.0.2", "4.0.3", "4.0.5", "4.0.6", "4.0.7", "4.0.8", "4.0.9", "4.0.10"}
+		supportedVersions := []string{"4.1.0", "4.1.1", "4.1.2"}
 
 		if !slices.Contains(supportedVersions, netboxVersion) {
 			// Currently, there is no way to test these warnings. There is an issue to track this: https://github.com/hashicorp/terraform-plugin-sdk/issues/864
diff --git a/netbox/resource_netbox_virtual_machine.go b/netbox/resource_netbox_virtual_machine.go
index 2d1ae4c7..faa65707 100644
--- a/netbox/resource_netbox_virtual_machine.go
+++ b/netbox/resource_netbox_virtual_machine.go
@@ -153,7 +153,7 @@ func resourceNetboxVirtualMachineCreate(ctx context.Context, d *schema.ResourceD
 
 	diskSizeValue, ok := d.GetOk("disk_size_gb")
 	if ok {
-		diskSize := int64(diskSizeValue.(int))
+		diskSize := int64(diskSizeValue.(int)) * 1000
 		data.Disk = &diskSize
 	}
 
@@ -308,7 +308,10 @@ func resourceNetboxVirtualMachineRead(ctx context.Context, d *schema.ResourceDat
 		d.Set("vcpus", nil)
 	}
 	d.Set("memory_mb", vm.Memory)
-	d.Set("disk_size_gb", vm.Disk)
+	if vm.Disk != nil {
+		diskSizeGb := *vm.Disk / 1000
+		d.Set("disk_size_gb", diskSizeGb)
+	}
 	if vm.Status != nil {
 		d.Set("status", vm.Status.Value)
 	} else {
diff --git a/templates/index.md.tmpl b/templates/index.md.tmpl
index cd7908b3..1087cc63 100644
--- a/templates/index.md.tmpl
+++ b/templates/index.md.tmpl
@@ -16,7 +16,8 @@ Netbox often makes breaking API changes even in non-major releases. Check the ta
 
 | Netbox version  | Provider version |
 | --------------- | ---------------- |
-| v4.0.0 - 4.0.10 | v3.9.0 and up    |
+| v4.1.0 - 4.1.2  | v3.10.0 and up   |
+| v4.0.0 - 4.0.10 | v3.9.0 - 3.9.1   |
 | v3.7.0 - 3.7.8  | v3.8.0 - 3.8.9   |
 | v3.6.0 - 3.6.9  | v3.7.0 - 3.7.7   |
 | v3.5.1 - 3.5.9  | v3.6.x           |