diff --git a/apitest.go b/apitest.go
index 5db3e46..45d7e36 100644
--- a/apitest.go
+++ b/apitest.go
@@ -322,7 +322,7 @@ type Response struct {
 	jsonPathExpression string
 	jsonPathAssert     func(interface{})
 	apiTest            *APITest
-	assert             Assert
+	assert             []Assert
 }
 
 // Assert is a user defined custom assertion function
@@ -378,7 +378,7 @@ func (r *Response) Status(s int) *Response {
 // Assert allows the consumer to provide a user defined function containing their own
 // custom assertions
 func (r *Response) Assert(fn func(*http.Response, *http.Request) error) *Response {
-	r.assert = fn
+	r.assert = append(r.assert, fn)
 	return r.apiTest.response
 }
 
@@ -530,13 +530,22 @@ func (a *APITest) run() {
 	a.assertResponse(res)
 	a.assertHeaders(res)
 	a.assertCookies(res)
+	err := a.assertFunc(res, req)
+	if err != nil {
+		a.t.Fatal(err.Error())
+	}
+}
 
-	if a.response.assert != nil {
-		err := a.response.assert(res.Result(), req)
-		if err != nil {
-			a.t.Fatal(err.Error())
+func (a *APITest) assertFunc(res *httptest.ResponseRecorder, req *http.Request) error {
+	if len(a.response.assert) > 0 {
+		for _, assertFn := range a.response.assert {
+			err := assertFn(res.Result(), req)
+			if err != nil {
+				return err
+			}
 		}
 	}
+	return nil
 }
 
 func (a *APITest) runTest() (*httptest.ResponseRecorder, *http.Request) {
diff --git a/apitest_test.go b/apitest_test.go
index 17bceab..2805c0e 100644
--- a/apitest_test.go
+++ b/apitest_test.go
@@ -2,6 +2,7 @@ package apitest
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"github.com/stretchr/testify/assert"
 	"io/ioutil"
@@ -410,6 +411,40 @@ func TestApiTest_CustomAssert(t *testing.T) {
 		End()
 }
 
+func TestApiTest_SupportsMultipleCustomAsserts(t *testing.T) {
+	test := New().
+		Patch("/hello").
+		Expect(t).
+		Assert(IsSuccess).
+		Assert(IsSuccess)
+
+	assert.Len(t, test.assert, 2)
+}
+
+func TestApiTest_AssertFunc(t *testing.T) {
+	tests := []struct {
+		statusCode  int
+		expectedErr error
+	}{
+		{200, nil},
+		{400, errors.New("not success. Status code=400")},
+	}
+	for _, test := range tests {
+		t.Run(fmt.Sprintf("status: %d", test.statusCode), func(t *testing.T) {
+			res := httptest.NewRecorder()
+			res.Code = test.statusCode
+			apitTest := New().
+				Patch("/hello").
+				Expect(t).
+				Assert(IsSuccess)
+
+			err := apitTest.apiTest.assertFunc(res, nil)
+
+			assert.Equal(t, test.expectedErr, err)
+		})
+	}
+}
+
 func TestApiTest_Report(t *testing.T) {
 	getUser := NewMock().
 		Get("http://localhost:8080").
diff --git a/assert.go b/assert.go
index b045b3e..0fb8b33 100644
--- a/assert.go
+++ b/assert.go
@@ -2,8 +2,8 @@ package apitest
 
 import (
 	"errors"
+	"fmt"
 	"net/http"
-	"strconv"
 )
 
 // IsSuccess is a convenience function to assert on a range of happy path status codes
@@ -11,7 +11,7 @@ var IsSuccess Assert = func(response *http.Response, request *http.Request) erro
 	if response.StatusCode >= 200 && response.StatusCode < 400 {
 		return nil
 	}
-	return errors.New("not a client error. Status code=" + strconv.Itoa(response.StatusCode))
+	return errors.New(fmt.Sprintf("not success. Status code=%d", response.StatusCode))
 }
 
 // IsClientError is a convenience function to assert on a range of client error status codes
@@ -19,7 +19,7 @@ var IsClientError Assert = func(response *http.Response, request *http.Request)
 	if response.StatusCode >= 400 && response.StatusCode < 500 {
 		return nil
 	}
-	return errors.New("not a client error. Status code=" + strconv.Itoa(response.StatusCode))
+	return errors.New(fmt.Sprintf("not a client error. Status code=%d", response.StatusCode))
 }
 
 // IsServerError is a convenience function to assert on a range of server error status codes
@@ -27,5 +27,5 @@ var IsServerError Assert = func(response *http.Response, request *http.Request)
 	if response.StatusCode >= 500 {
 		return nil
 	}
-	return errors.New("not a server error. Status code=" + strconv.Itoa(response.StatusCode))
+	return errors.New(fmt.Sprintf("not a server error. Status code=%d", response.StatusCode))
 }