diff --git a/helper/resource/testing.go b/helper/resource/testing.go
index 23af81096..5f08c2a3f 100644
--- a/helper/resource/testing.go
+++ b/helper/resource/testing.go
@@ -354,21 +354,15 @@ func Test(t TestT, c TestCase) {
 // Any errors are stored so that they can be returned by the factory in
 // terraform to match non-test behavior.
 func testProviderFactories(c TestCase) (map[string]terraform.ResourceProviderFactory, error) {
-	ctxProviders := make(map[string]terraform.ResourceProviderFactory)
-
+	ctxProviders := c.ProviderFactories // make(map[string]terraform.ResourceProviderFactory)
+	if ctxProviders == nil {
+		ctxProviders = make(map[string]terraform.ResourceProviderFactory)
+	}
 	// add any fixed providers
 	for k, p := range c.Providers {
 		ctxProviders[k] = terraform.ResourceProviderFactoryFixed(p)
 	}
 
-	// call any factory functions and store the result.
-	for k, pf := range c.ProviderFactories {
-		p, err := pf()
-		ctxProviders[k] = func() (terraform.ResourceProvider, error) {
-			return p, err
-		}
-	}
-
 	// reset the providers if needed
 	for k, pf := range ctxProviders {
 		// we can ignore any errors here, if we don't have a provider to reset