Redirect from asp.net web api post action

Sure:

public HttpResponseMessage Post()
{
    // ... do the job

    // now redirect
    var response = Request.CreateResponse(HttpStatusCode.Moved);
    response.Headers.Location = new Uri("http://www.abcmvc.com");
    return response;
}

Here is another way you can get to the root of your website without hard coding the url:

var response = Request.CreateResponse(HttpStatusCode.Moved);
string fullyQualifiedUrl = Request.RequestUri.GetLeftPart(UriPartial.Authority);
response.Headers.Location = new Uri(fullyQualifiedUrl);

Note: Will only work if both your MVC website and WebApi are on the same URL

    [HttpGet]
    public RedirectResult Get()
    {
        return RedirectPermanent("https://www.google.com");
    }

You can check this

[Route("Report/MyReport")]
public IHttpActionResult GetReport()
{

   string url = "https://localhost:44305/Templates/ReportPage.html";

   System.Uri uri = new System.Uri(url);

   return Redirect(uri);
}