diff --git a/internal/provider/group_resource.go b/internal/provider/group_resource.go
index 1afaebb..46bc6c9 100644
--- a/internal/provider/group_resource.go
+++ b/internal/provider/group_resource.go
@@ -240,19 +240,24 @@ func (r *GroupResource) Update(ctx context.Context, req resource.UpdateRequest,
 		resp.Diagnostics.AddError("Client Error", fmt.Sprintf("Unable to get group, got error: %s", err))
 		return
 	}
-	var newMembers []string
-	resp.Diagnostics.Append(
-		data.Members.ElementsAs(ctx, &newMembers, false)...,
-	)
-	if resp.Diagnostics.HasError() {
-		return
-	}
 	var add []string
 	var remove []string
 	if !data.Members.IsNull() {
-		add, remove = memberDiff(group.Members, newMembers)
+		var plannedMembers []UUID
+		resp.Diagnostics.Append(
+			data.Members.ElementsAs(ctx, &plannedMembers, false)...,
+		)
+		if resp.Diagnostics.HasError() {
+			return
+		}
+		curMembers := make([]uuid.UUID, 0, len(group.Members))
+		for _, member := range group.Members {
+			curMembers = append(curMembers, member.ID)
+		}
+		add, remove = memberDiff(curMembers, plannedMembers)
 	}
 	tflog.Trace(ctx, "updating group", map[string]any{
+		"id":              groupID,
 		"new_members":     add,
 		"removed_members": remove,
 		"new_name":        data.Name,
@@ -293,7 +298,9 @@ func (r *GroupResource) Delete(ctx context.Context, req resource.DeleteRequest,
 	client := r.data.Client
 	groupID := data.ID.ValueUUID()
 
-	tflog.Trace(ctx, "deleting group")
+	tflog.Trace(ctx, "deleting group", map[string]any{
+		"id": groupID,
+	})
 	err := client.DeleteGroup(ctx, groupID)
 	if err != nil {
 		resp.Diagnostics.AddError("Client Error", fmt.Sprintf("Unable to delete group, got error: %s", err))
@@ -320,24 +327,3 @@ func (r *GroupResource) ImportState(ctx context.Context, req resource.ImportStat
 	}
 	resource.ImportStatePassthroughID(ctx, path.Root("id"), req, resp)
 }
-
-func memberDiff(curMembers []codersdk.ReducedUser, newMembers []string) (add, remove []string) {
-	curSet := make(map[string]struct{}, len(curMembers))
-	newSet := make(map[string]struct{}, len(newMembers))
-
-	for _, user := range curMembers {
-		curSet[user.ID.String()] = struct{}{}
-	}
-	for _, userID := range newMembers {
-		newSet[userID] = struct{}{}
-		if _, exists := curSet[userID]; !exists {
-			add = append(add, userID)
-		}
-	}
-	for _, user := range curMembers {
-		if _, exists := newSet[user.ID.String()]; !exists {
-			remove = append(remove, user.ID.String())
-		}
-	}
-	return add, remove
-}
diff --git a/internal/provider/group_resource_test.go b/internal/provider/group_resource_test.go
index 2b90868..b049976 100644
--- a/internal/provider/group_resource_test.go
+++ b/internal/provider/group_resource_test.go
@@ -62,49 +62,66 @@ func TestAccGroupResource(t *testing.T) {
 	cfg3 := cfg2
 	cfg3.Members = nil
 
-	resource.Test(t, resource.TestCase{
-		PreCheck:                 func() { testAccPreCheck(t) },
-		ProtoV6ProviderFactories: testAccProtoV6ProviderFactories,
-		Steps: []resource.TestStep{
-			// Create and Read
-			{
-				Config: cfg1.String(t),
-				Check: resource.ComposeAggregateTestCheckFunc(
-					resource.TestCheckResourceAttr("coderd_group.test", "name", "example-group"),
-					resource.TestCheckResourceAttr("coderd_group.test", "display_name", "Example Group"),
-					resource.TestCheckResourceAttr("coderd_group.test", "avatar_url", "https://google.com"),
-					resource.TestCheckResourceAttr("coderd_group.test", "quota_allowance", "100"),
-					resource.TestCheckResourceAttr("coderd_group.test", "organization_id", firstUser.OrganizationIDs[0].String()),
-					resource.TestCheckResourceAttr("coderd_group.test", "members.#", "1"),
-					resource.TestCheckResourceAttr("coderd_group.test", "members.0", user1.ID.String()),
-				),
+	t.Run("CreateImportUpdateReadOk", func(t *testing.T) {
+		resource.Test(t, resource.TestCase{
+			PreCheck:                 func() { testAccPreCheck(t) },
+			ProtoV6ProviderFactories: testAccProtoV6ProviderFactories,
+			Steps: []resource.TestStep{
+				// Create and Read
+				{
+					Config: cfg1.String(t),
+					Check: resource.ComposeAggregateTestCheckFunc(
+						resource.TestCheckResourceAttr("coderd_group.test", "name", "example-group"),
+						resource.TestCheckResourceAttr("coderd_group.test", "display_name", "Example Group"),
+						resource.TestCheckResourceAttr("coderd_group.test", "avatar_url", "https://google.com"),
+						resource.TestCheckResourceAttr("coderd_group.test", "quota_allowance", "100"),
+						resource.TestCheckResourceAttr("coderd_group.test", "organization_id", firstUser.OrganizationIDs[0].String()),
+						resource.TestCheckResourceAttr("coderd_group.test", "members.#", "1"),
+						resource.TestCheckResourceAttr("coderd_group.test", "members.0", user1.ID.String()),
+					),
+				},
+				// Import
+				{
+					Config:                  cfg1.String(t),
+					ResourceName:            "coderd_group.test",
+					ImportState:             true,
+					ImportStateVerify:       true,
+					ImportStateVerifyIgnore: []string{"members"},
+				},
+				// Update and Read
+				{
+					Config: cfg2.String(t),
+					Check: resource.ComposeAggregateTestCheckFunc(
+						resource.TestCheckResourceAttr("coderd_group.test", "name", "example-group-new"),
+						resource.TestCheckResourceAttr("coderd_group.test", "display_name", "Example Group New"),
+						resource.TestCheckResourceAttr("coderd_group.test", "members.#", "1"),
+						resource.TestCheckResourceAttr("coderd_group.test", "members.0", user2.ID.String()),
+					),
+				},
+				// Unmanaged members
+				{
+					Config: cfg3.String(t),
+					Check: resource.ComposeAggregateTestCheckFunc(
+						resource.TestCheckNoResourceAttr("coderd_group.test", "members"),
+					),
+				},
 			},
-			// Import
-			{
-				Config:                  cfg1.String(t),
-				ResourceName:            "coderd_group.test",
-				ImportState:             true,
-				ImportStateVerify:       true,
-				ImportStateVerifyIgnore: []string{"members"},
-			},
-			// Update and Read
-			{
-				Config: cfg2.String(t),
-				Check: resource.ComposeAggregateTestCheckFunc(
-					resource.TestCheckResourceAttr("coderd_group.test", "name", "example-group-new"),
-					resource.TestCheckResourceAttr("coderd_group.test", "display_name", "Example Group New"),
-					resource.TestCheckResourceAttr("coderd_group.test", "members.#", "1"),
-					resource.TestCheckResourceAttr("coderd_group.test", "members.0", user2.ID.String()),
-				),
-			},
-			// Unmanaged members
-			{
-				Config: cfg3.String(t),
-				Check: resource.ComposeAggregateTestCheckFunc(
-					resource.TestCheckNoResourceAttr("coderd_group.test", "members"),
-				),
+		})
+	})
+
+	t.Run("CreateUnmanagedMembersOk", func(t *testing.T) {
+		resource.Test(t, resource.TestCase{
+			PreCheck:                 func() { testAccPreCheck(t) },
+			ProtoV6ProviderFactories: testAccProtoV6ProviderFactories,
+			Steps: []resource.TestStep{
+				{
+					Config: cfg3.String(t),
+					Check: resource.ComposeAggregateTestCheckFunc(
+						resource.TestCheckNoResourceAttr("coderd_group.test", "members"),
+					),
+				},
 			},
-		},
+		})
 	})
 }
 
diff --git a/internal/provider/util.go b/internal/provider/util.go
index 75f5196..bb1386e 100644
--- a/internal/provider/util.go
+++ b/internal/provider/util.go
@@ -6,6 +6,8 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+
+	"github.com/google/uuid"
 )
 
 func PtrTo[T any](v T) *T {
@@ -76,3 +78,26 @@ func computeDirectoryHash(directory string) (string, error) {
 	}
 	return hex.EncodeToString(hash.Sum(nil)), nil
 }
+
+// memberDiff returns the members to add and remove from the group, given the current members and the planned members.
+// plannedMembers is deliberately our custom type, as Terraform cannot automatically produce `[]uuid.UUID` from a set.
+func memberDiff(curMembers []uuid.UUID, plannedMembers []UUID) (add, remove []string) {
+	curSet := make(map[uuid.UUID]struct{}, len(curMembers))
+	planSet := make(map[uuid.UUID]struct{}, len(plannedMembers))
+
+	for _, userID := range curMembers {
+		curSet[userID] = struct{}{}
+	}
+	for _, plannedUserID := range plannedMembers {
+		planSet[plannedUserID.ValueUUID()] = struct{}{}
+		if _, exists := curSet[plannedUserID.ValueUUID()]; !exists {
+			add = append(add, plannedUserID.ValueString())
+		}
+	}
+	for _, curUserID := range curMembers {
+		if _, exists := planSet[curUserID]; !exists {
+			remove = append(remove, curUserID.String())
+		}
+	}
+	return add, remove
+}