How to query between two dates using Laravel and Eloquent?

Another option if your field is datetime instead of date (although it works for both cases):

$fromDate = "2016-10-01";
$toDate   = "2016-10-31";

$reservations = Reservation::whereRaw(
  "(reservation_from >= ? AND reservation_from <= ?)", 
  [
     $fromDate ." 00:00:00", 
     $toDate ." 23:59:59"
  ]
)->get();

The whereBetween method verifies that a column's value is between two values.

$from = date('2018-01-01');
$to = date('2018-05-02');

Reservation::whereBetween('reservation_from', [$from, $to])->get();

In some cases you need to add date range dynamically. Based on @Anovative's comment you can do this:

Reservation::all()->filter(function($item) {
  if (Carbon::now()->between($item->from, $item->to)) {
    return $item;
  }
});

If you would like to add more condition then you can use orWhereBetween. If you would like to exclude a date interval then you can use whereNotBetween .

Reservation::whereBetween('reservation_from', [$from1, $to1])
  ->orWhereBetween('reservation_to', [$from2, $to2])
  ->whereNotBetween('reservation_to', [$from3, $to3])
  ->get();

Other useful where clauses: whereIn, whereNotIn, whereNull, whereNotNull, whereDate, whereMonth, whereDay, whereYear, whereTime, whereColumn , whereExists, whereRaw.

Laravel docs about Where Clauses.