> ## Documentation Index
> Fetch the complete documentation index at: https://docs.flystack.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Flight Delays

> Monitor live flight delays worldwide or filter by airport, airline, or flight.

<Note>
  Beta: This endpoint reflects live delays for departing or arriving flights. Coverage may vary.
</Note>

Real-time delay data helps you monitor disruption anywhere in the world, or focus on a specific airport/route. It’s especially useful for airport transfers, travel insurance, and delay compensation workflows.

### Authentication

<ParamField header="x-api-key" type="string" required={true}>
  Your FlyStack API token. You can create one from the dashboard (see [Authentication](/authentication)).
</ParamField>

### Query parameters

#### Required

<ParamField query="delay" type="number" required={true}>
  Minimum delay (in minutes). Must be greater than 30.
</ParamField>

<ParamField query="type" type="string" required={true}>
  Flight type:

  * `departures`
  * `arrivals`
</ParamField>

#### Optional filters

<ParamField query="dep_iata" type="string" required={false}>
  Filter by departure airport IATA code.
</ParamField>

<ParamField query="dep_icao" type="string" required={false}>
  Filter by departure airport ICAO code.
</ParamField>

<ParamField query="arr_iata" type="string" required={false}>
  Filter by arrival airport IATA code.
</ParamField>

<ParamField query="arr_icao" type="string" required={false}>
  Filter by arrival airport ICAO code.
</ParamField>

<ParamField query="airline_icao" type="string" required={false}>
  Filter by airline ICAO code.
</ParamField>

<ParamField query="airline_iata" type="string" required={false}>
  Filter by airline IATA code.
</ParamField>

<ParamField query="flight_icao" type="string" required={false}>
  Filter by flight ICAO code-number.
</ParamField>

<ParamField query="flight_iata" type="string" required={false}>
  Filter by flight IATA code-number.
</ParamField>

<ParamField query="flight_number" type="string" required={false}>
  Filter by flight number only.
</ParamField>

#### Response shaping & pagination

<ParamField query="_fields" type="string" required={false}>
  Comma-separated list of fields to return (e.g., `airline_iata,flight_number`).
</ParamField>

<ParamField query="limit" type="number" required={false}>
  Max number of results per response (limits may depend on your plan).
</ParamField>

<ParamField query="offset" type="number" required={false}>
  Pagination offset (0+). Use with `limit` when a response indicates there are more results.
</ParamField>

### Response

The endpoint returns a list of delayed flights.

#### Delay response fields

<ResponseField type="array">
  <ResponseField type="object">
    <Note>
      This response reuses the schedule-style fields (airline/flight codes, airports, terminals/gates, times). The key delay field is `delayed`.
    </Note>

    <Expandable title="Core identifiers" defaultOpen={false}>
      <ResponseField name="airline_iata" type="string">
        Airline IATA code.
      </ResponseField>

      <ResponseField name="airline_icao" type="string">
        Airline ICAO code.
      </ResponseField>

      <ResponseField name="flight_iata" type="string">
        Flight IATA code-number.
      </ResponseField>

      <ResponseField name="flight_icao" type="string">
        Flight ICAO code-number.
      </ResponseField>

      <ResponseField name="flight_number" type="string">
        Flight number only.
      </ResponseField>
    </Expandable>

    <Expandable title="Airports" defaultOpen={false}>
      <ResponseField name="dep_iata" type="string">
        Departure airport IATA code.
      </ResponseField>

      <ResponseField name="dep_icao" type="string">
        Departure airport ICAO code.
      </ResponseField>

      <ResponseField name="arr_iata" type="string">
        Arrival airport IATA code.
      </ResponseField>

      <ResponseField name="arr_icao" type="string">
        Arrival airport ICAO code.
      </ResponseField>

      <ResponseField name="dep_terminal" type="string">
        Estimated departure terminal (when available).
      </ResponseField>

      <ResponseField name="dep_gate" type="string">
        Estimated departure gate (when available).
      </ResponseField>

      <ResponseField name="arr_terminal" type="string">
        Estimated arrival terminal (when available).
      </ResponseField>

      <ResponseField name="arr_gate" type="string">
        Estimated arrival gate (when available).
      </ResponseField>

      <ResponseField name="arr_baggage" type="string">
        Estimated baggage belt (when available).
      </ResponseField>
    </Expandable>

    <Expandable title="Times & delay" defaultOpen={false}>
      <ResponseField name="dep_time" type="string">
        Scheduled departure time (local).
      </ResponseField>

      <ResponseField name="dep_time_ts" type="number">
        Scheduled departure time (unix).
      </ResponseField>

      <ResponseField name="dep_time_utc" type="string">
        Scheduled departure time (UTC).
      </ResponseField>

      <ResponseField name="dep_estimated" type="string">
        Estimated departure time (local, when available).
      </ResponseField>

      <ResponseField name="dep_estimated_ts" type="number">
        Estimated departure time (unix, when available).
      </ResponseField>

      <ResponseField name="dep_estimated_utc" type="string">
        Estimated departure time (UTC, when available).
      </ResponseField>

      <ResponseField name="arr_time" type="string">
        Scheduled arrival time (local).
      </ResponseField>

      <ResponseField name="arr_time_ts" type="number">
        Scheduled arrival time (unix).
      </ResponseField>

      <ResponseField name="arr_time_utc" type="string">
        Scheduled arrival time (UTC).
      </ResponseField>

      <ResponseField name="arr_estimated" type="string">
        Estimated arrival time (local, when available).
      </ResponseField>

      <ResponseField name="arr_estimated_ts" type="number">
        Estimated arrival time (unix, when available).
      </ResponseField>

      <ResponseField name="arr_estimated_utc" type="string">
        Estimated arrival time (UTC, when available).
      </ResponseField>

      <ResponseField name="delayed" type="number">
        Estimated delay time (minutes).
      </ResponseField>
    </Expandable>
  </ResponseField>
</ResponseField>

<ResponseExample>
  ```json Response theme={null}
  [
    {
      "airline_iata": "BA",
      "airline_icao": "BAW",
      "flight_iata": "BA6984",
      "flight_icao": "BAW6984",
      "flight_number": "6984",
      "cs_airline_iata": "AA",
      "cs_flight_number": "2421",
      "cs_flight_iata": "AA2421",
      "dep_iata": "MIA",
      "dep_icao": "KMIA",
      "dep_terminal": "C",
      "dep_gate": "E4",
      "dep_time": "2021-07-14 19:53",
      "dep_time_ts": 1626306780,
      "dep_time_utc": "2021-07-14 23:53",
      "dep_estimated": "2021-07-14 22:10",
      "dep_estimated_ts": 1626315000,
      "dep_estimated_utc": "2021-07-15 02:10",
      "arr_iata": "SFO",
      "arr_icao": "KSFO",
      "arr_terminal": "1",
      "arr_gate": "B24",
      "arr_baggage": "1",
      "arr_time": "2021-07-14 22:52",
      "arr_time_ts": 1626328320,
      "arr_time_utc": "2021-07-15 05:52",
      "arr_estimated": "2021-07-15 01:09",
      "arr_estimated_ts": 1626336540,
      "arr_estimated_utc": "2021-07-15 08:09",
      "status": "scheduled",
      "duration": 359,
      "delayed": 137
    }
  ]
  ```
</ResponseExample>

### See also

* [Flight Lookup API](/api-reference/endpoints/flight)
* [Flight Schedules API](/api-reference/endpoints/schedules)
* [Real-Time Flights API](/api-reference/endpoints/flights)
* [Routes Dataset API](/api-reference/endpoints/routes)