---
title: "Porting Days and Supported Hours"
slug: "porting-days-and-supported-hours"
tags: ["calltower", "public"]
updated: 2026-07-27T12:58:33Z
published: 2026-07-27T12:58:33Z
canonical: "learn.calltower.com/porting-days-and-supported-hours"
stale: true
---

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

# Porting Days and Supported Hours

To ensure a successful porting experience and minimize the risk of service disruption, all number porting activities are completed **within supported carrier hours**. Our porting schedule is intentionally aligned with **both winning and losing carrier availability** to ensure rapid response if issues arise during or immediately after a port.

## Standard Porting Hours for US/CAN numbers

All **US/ CAN** number ports are scheduled within the following supported windows (Eastern Time):

- **Monday – Thursday:** **8:00 – 5:00 PM ET**

- **Friday:** **8:00 AM – 2:00 PM ET**

## Why These Hours Are Enforced

Carrier support availability — **both on the gaining (winning) and losing carrier side** — is limited outside standard business hours. While availability varies by carrier, most providers have **reduced or no port-level support after 5:00–6:00 PM ET**, and significantly limited support late Fridays and over weekends.

Porting outside of supported hours increases risk, including:

- **Inability to reach the losing carrier** to:
  - Obtain real-time concurrence on the port
  - Troubleshoot unexpected rejections or delays
- **Delayed removal of translations or routing** on the losing carrier’s network, which can result in:
  - One-way calling
  - Intermittent call failures
  - Calls continuing to route to the old provider
- Limited or unavailable carrier escalation paths if issues arise
- Extended **out of service exposure until the next business day**

To mitigate these risks, all ports are scheduled **only during hours when both carriers are actively supporting port activity and post port validation**.

## Friday Porting Limitations

For additional risk mitigation and carrier alignment:

- **Carrier partners do not support project ports past 2:00 PM ET on Fridays**
- As a result, **all Friday porting concludes at 2:00 PM ET**

This limited Friday window ensures there is sufficient time to:

- Obtain full concurrence from the losing carrier
- Confirm translations are removed and routing is properly updated
- Validate call completion post port
- Address any issues *before* weekend carrier support limitations begin

## Key Notes

- Port requests scheduled outside supported hours will be moved to the **next available business day**
- These hours apply to **both standard and project ports**
- Porting outside supported hours is not recommended due to the increased risk of service disruption and delayed resolution

## ⚠ Supported Porting Hours

Ports are completed only during carrier supported hours to ensure both the winning and losing carrier are available for concurrence, translation removal, and immediate issue resolution.