Is it possible to somehow append json objects onto a URLSearchParams object? So instead of: urlSearchParams.append('search', 'person'); it's: urlSearchParams.append({search: "person"}); My answer courtesy of Darshak Gajjar's answer Can use json objects via this way: let test_this = [{"search": "person"}, { search: "another person"}]; var json = JSON.stringify(test_this); urlSearchParams.append("myobj", json); return this.http.post(this.post_url, urlSearchParams, options) //options being your own RequestOptions Continue reading...