diff --git a/internal/cloud/backend.go b/internal/cloud/backend.go
index 2a0549689..6fd6e6ace 100644
--- a/internal/cloud/backend.go
+++ b/internal/cloud/backend.go
@@ -151,12 +151,7 @@ func (b *Cloud) PrepareConfig(obj cty.Value) (cty.Value, tfdiags.Diagnostics) {
 	}
 
 	if val := obj.GetAttr("organization"); val.IsNull() || val.AsString() == "" {
-		diags = diags.Append(tfdiags.AttributeValue(
-			tfdiags.Error,
-			"Invalid organization value",
-			`The "organization" attribute value must not be empty.`,
-			cty.Path{cty.GetAttrStep{Name: "organization"}},
-		))
+		diags = diags.Append(invalidOrganizationConfigMissingValue)
 	}
 
 	var name, prefix string
@@ -171,22 +166,12 @@ func (b *Cloud) PrepareConfig(obj cty.Value) (cty.Value, tfdiags.Diagnostics) {
 
 	// Make sure that we have either a workspace name or a prefix.
 	if name == "" && prefix == "" {
-		diags = diags.Append(tfdiags.AttributeValue(
-			tfdiags.Error,
-			"Invalid workspaces configuration",
-			`Either workspace "name" or "prefix" is required.`,
-			cty.Path{cty.GetAttrStep{Name: "workspaces"}},
-		))
+		diags = diags.Append(invalidWorkspaceConfigMissingValues)
 	}
 
 	// Make sure that only one of workspace name or a prefix is configured.
 	if name != "" && prefix != "" {
-		diags = diags.Append(tfdiags.AttributeValue(
-			tfdiags.Error,
-			"Invalid workspaces configuration",
-			`Only one of workspace "name" or "prefix" is allowed.`,
-			cty.Path{cty.GetAttrStep{Name: "workspaces"}},
-		))
+		diags = diags.Append(invalidWorkspaceConfigMisconfiguration)
 	}
 
 	return obj, diags
diff --git a/internal/cloud/backend_test.go b/internal/cloud/backend_test.go
index 7862ad0a3..66c3f5bef 100644
--- a/internal/cloud/backend_test.go
+++ b/internal/cloud/backend_test.go
@@ -39,6 +39,65 @@ func TestCloud_backendNoDefault(t *testing.T) {
 	backend.TestBackendStates(t, b)
 }
 
+func TestCloud_PrepareConfig(t *testing.T) {
+	cases := map[string]struct {
+		config      cty.Value
+		expectedErr string
+	}{
+		"null organization": {
+			config: cty.ObjectVal(map[string]cty.Value{
+				"organization": cty.NullVal(cty.String),
+				"workspaces": cty.ObjectVal(map[string]cty.Value{
+					"name":   cty.StringVal("prod"),
+					"prefix": cty.NullVal(cty.String),
+				}),
+			}),
+			expectedErr: `Invalid organization value: The "organization" attribute value must not be empty.`,
+		},
+		"null workspace": {
+			config: cty.ObjectVal(map[string]cty.Value{
+				"organization": cty.StringVal("org"),
+				"workspaces":   cty.NullVal(cty.String),
+			}),
+			expectedErr: `Invalid workspaces configuration: Either workspace "name" or "prefix" is required.`,
+		},
+		"workspace: empty name and empty prefix": {
+			config: cty.ObjectVal(map[string]cty.Value{
+				"organization": cty.StringVal("org"),
+				"workspaces": cty.ObjectVal(map[string]cty.Value{
+					"name":   cty.NullVal(cty.String),
+					"prefix": cty.NullVal(cty.String),
+				}),
+			}),
+			expectedErr: `Invalid workspaces configuration: Either workspace "name" or "prefix" is required.`,
+		},
+		"workspace: name and prefix present": {
+			config: cty.ObjectVal(map[string]cty.Value{
+				"organization": cty.StringVal("org"),
+				"workspaces": cty.ObjectVal(map[string]cty.Value{
+					"name":   cty.StringVal("prod"),
+					"prefix": cty.StringVal("app-"),
+				}),
+			}),
+			expectedErr: `Invalid workspaces configuration: Only one of workspace "name" or "prefix" is allowed.`,
+		},
+	}
+
+	for name, tc := range cases {
+		s := testServer(t)
+		b := New(testDisco(s))
+
+		// Validate
+		_, valDiags := b.PrepareConfig(tc.config)
+		if valDiags.Err() != nil && tc.expectedErr != "" {
+			actualErr := valDiags.Err().Error()
+			if !strings.Contains(actualErr, tc.expectedErr) {
+				t.Fatalf("%s: unexpected validation result: %v", name, valDiags.Err())
+			}
+		}
+	}
+}
+
 func TestCloud_config(t *testing.T) {
 	cases := map[string]struct {
 		config  cty.Value
diff --git a/internal/cloud/errors.go b/internal/cloud/errors.go
new file mode 100644
index 000000000..273f8a157
--- /dev/null
+++ b/internal/cloud/errors.go
@@ -0,0 +1,29 @@
+package cloud
+
+import (
+	"github.com/hashicorp/terraform/internal/tfdiags"
+	"github.com/zclconf/go-cty/cty"
+)
+
+var (
+	invalidOrganizationConfigMissingValue = tfdiags.AttributeValue(
+		tfdiags.Error,
+		"Invalid organization value",
+		`The "organization" attribute value must not be empty.`,
+		cty.Path{cty.GetAttrStep{Name: "organization"}},
+	)
+
+	invalidWorkspaceConfigMissingValues = tfdiags.AttributeValue(
+		tfdiags.Error,
+		"Invalid workspaces configuration",
+		`Either workspace "name" or "prefix" is required.`,
+		cty.Path{cty.GetAttrStep{Name: "workspaces"}},
+	)
+
+	invalidWorkspaceConfigMisconfiguration = tfdiags.AttributeValue(
+		tfdiags.Error,
+		"Invalid workspaces configuration",
+		`Only one of workspace "name" or "prefix" is allowed.`,
+		cty.Path{cty.GetAttrStep{Name: "workspaces"}},
+	)
+)