---
title: "delay(for:tolerance:scheduler:options:)"
framework: combine
role: symbol
role_heading: Instance Method
path: "combine/publisher/delay(for:tolerance:scheduler:options:)"
---

# delay(for:tolerance:scheduler:options:)

Delays delivery of all output to the downstream receiver by a specified amount of time on a particular scheduler.

## Declaration

```swift
func delay<S>(for interval: S.SchedulerTimeType.Stride, tolerance: S.SchedulerTimeType.Stride? = nil, scheduler: S, options: S.SchedulerOptions? = nil) -> Publishers.Delay<Self, S> where S : Scheduler
```

## Parameters

- `interval`: The amount of time to delay.
- `tolerance`: The allowed tolerance in delivering delayed events. The Delay publisher may deliver elements this much sooner or later than the interval specifies.
- `scheduler`: The scheduler to deliver the delayed events.
- `options`: Options relevant to the scheduler’s behavior.

## Return Value

Return Value A publisher that delays delivery of elements and completion to the downstream receiver.

## Discussion

Discussion Use delay(for:tolerance:scheduler:options:) when you need to delay the delivery of elements to a downstream by a specified amount of time. In this example, a Timer publishes an event every second. The delay(for:tolerance:scheduler:options:) operator holds the delivery of the initial element for 3 seconds (±0.5 seconds), after which each element is delivered to the downstream on the main run loop after the specified delay: let df = DateFormatter() df.dateStyle = .none df.timeStyle = .long cancellable = Timer.publish(every: 1.0, on: .main, in: .default)     .autoconnect()     .handleEvents(receiveOutput: { date in         print ("Sending Timestamp \'\(df.string(from: date))\' to delay()")     })     .delay(for: .seconds(3), scheduler: RunLoop.main, options: .none)     .sink(         receiveCompletion: { print ("completion: \($0)", terminator: "\n") },         receiveValue: { value in             let now = Date()             print ("At \(df.string(from: now)) received  Timestamp \'\(df.string(from: value))\' sent: \(String(format: "%.2f", now.timeIntervalSince(value))) secs ago", terminator: "\n")         }     )

// Prints: //    Sending Timestamp '5:02:33 PM PDT' to delay() //    Sending Timestamp '5:02:34 PM PDT' to delay() //    Sending Timestamp '5:02:35 PM PDT' to delay() //    Sending Timestamp '5:02:36 PM PDT' to delay() //    At 5:02:36 PM PDT received  Timestamp '5:02:33 PM PDT' sent: 3.00 secs ago //    Sending Timestamp '5:02:37 PM PDT' to delay() //    At 5:02:37 PM PDT received  Timestamp '5:02:34 PM PDT' sent: 3.00 secs ago //    Sending Timestamp '5:02:38 PM PDT' to delay() //    At 5:02:38 PM PDT received  Timestamp '5:02:35 PM PDT' sent: 3.00 secs ago The delay affects the delivery of elements and completion, but not of the original subscription.

## See Also

### Controlling timing

- [measureInterval(using:options:)](combine/publisher/measureinterval(using:options:).md)
- [debounce(for:scheduler:options:)](combine/publisher/debounce(for:scheduler:options:).md)
- [throttle(for:scheduler:latest:)](combine/publisher/throttle(for:scheduler:latest:).md)
- [timeout(_:scheduler:options:customError:)](combine/publisher/timeout(_:scheduler:options:customerror:).md)