Reset select2 value and show placeholder

You must define the select2 as

$("#customers_select").select2({
    placeholder: "Select a customer",
    initSelection: function(element, callback) {                   
    }
});

To reset the select2

$("#customers_select").select2("val", "");

The accepted answer does not work in my case. I'm trying this, and it's working:

Define select2:

$("#customers_select").select2({
    placeholder: "Select a State",
    allowClear: true
});

or

$("#customers_select").select2({
    placeholder: "Select a State"
});

To reset:

$("#customers_select").val('').trigger('change')

or

$("#customers_select").empty().trigger('change')

Select2 has changed their API:

Select2: The select2("val") method has been deprecated and will be removed in later Select2 versions. Use $element.val() instead.

The best way to do this now is:

$('#your_select_input').val('');

Edit: December 2016 Comments suggest that the below is the updated way to do this:

$('#your_select_input').val([]);

The only thing can work for me is:

$('select2element').val(null).trigger("change")

I'm using version 4.0.3

Reference

According to Select2 Documentation

With Select2 version 4.0.9 this works for me:

$( "#myselect2" ).val('').trigger('change');