How to Switch Business Mobile Provider: Complete Guide

Published: 23 February 2026 • Compare The Networks

Switching your business mobile provider can save your company thousands of pounds per year -- but the process feels daunting when you have multiple lines, existing contracts, and the fear of downtime. The good news is that UK regulations make switching straightforward, and with proper planning, you can port all your numbers with zero disruption. This guide walks you through the entire process, from PAC codes to bulk porting and minimising downtime.

Why Businesses Switch Mobile Provider

The most common reasons UK businesses switch their mobile provider include:

• Cost savings -- out-of-contract rates are often higher than new customer deals. Switching can save 20-40% per line.
• Better coverage -- your team may have moved to new locations or taken on field workers in areas where your current network has poor signal
• Improved service -- poor customer support, billing errors, or slow issue resolution are common reasons for switching
• Better plans -- more data, included EU roaming, or 5G access on a competitor network
• Contract consolidation -- businesses that have accumulated lines across multiple providers want to bring everything under one account

Step-by-Step: How to Switch Your Business Mobile Provider

Step 1: Review Your Current Contracts

Before doing anything, gather information on all your existing lines:

• Contract end dates -- check when each line's minimum term expires. Lines out of contract can be switched immediately. Lines still within contract will incur early termination fees (ETFs).
• Monthly costs -- note what you are currently paying per line (ex-VAT) so you can make an accurate comparison
• Data usage -- check each line's actual data usage over the past 3-6 months. You may find some lines need more or less data than currently allocated.
• Any bolt-ons or add-ons -- international calling packs, roaming bolt-ons, insurance, or device warranties that may need replacing

Tip Log into your current provider's business portal to download the last 6 months of bills. This gives you the data you need to negotiate with new providers and ensures you choose the right plan for each line.

Step 2: Get Quotes from New Providers

Compare business mobile deals from all major UK networks. When requesting quotes, provide:

• Number of lines you are moving
• Data requirements per line
• Whether you need new handsets or SIM-only deals
• Any specific requirements (EU roaming, international calls, 5G, etc.)

Most networks offer significant discounts for multi-line business accounts. Tell each provider you are comparing multiple options -- this often triggers better pricing.

Step 3: Request PAC Codes

A PAC (Porting Authorisation Code) is a 9-character code that transfers your existing phone number to a new provider. Without a PAC, you would get a new number and lose your existing business numbers.

How to get a PAC code:

• Text method: Send "PAC" to 65075 from the mobile you want to port. Your current provider must reply within 60 seconds with your PAC code. This works for individual lines.
• Online: Log into your current provider's business portal and request PAC codes for each line
• Phone: Call your current provider's business support team and request PAC codes for all lines

PAC codes are valid for 30 days. If you do not use the code within 30 days, it expires and you will need to request a new one.

Step 4: Bulk PAC Codes for Multiple Lines

If you have 5 or more lines, requesting individual PAC codes by text is impractical. Instead:

1. Contact your current provider's business retention team and request bulk PAC codes for all lines on the account
2. They are legally obliged to provide them within one working day
3. You will receive a list of PAC codes -- one per line -- along with the associated phone numbers
4. Some providers issue a single "bulk PAC" reference that covers all lines on the account

Tip Your current provider will likely try to retain your business by offering a counter-offer or reduced rates. Listen to the offer -- sometimes it is genuinely competitive -- but do not feel pressured. You are legally entitled to your PAC codes regardless of any ongoing negotiation.

Step 5: Give PAC Codes to Your New Provider

Provide the PAC codes to your new business mobile provider when setting up your new account. They will handle the porting process. You will need to match each PAC code to the correct phone number.

Step 6: The Porting Process

Once your new provider submits the porting request, this is what happens:

• Day 1: New provider submits porting request to old provider
• Day 1-2: Old provider processes the request and confirms
• Porting day (usually within 1 working day): Your number transfers to the new network. There will be a brief period (typically 2-4 hours) where your service switches over. During this time, you may experience a short interruption.

The total process from giving your PAC code to the new provider to your number being active on the new network is typically one working day. Ofcom mandates that porting must be completed within one working day from the point the new provider submits the request.

Step 7: Verify Everything Works

After the port completes:

• Test outgoing calls from each line
• Have someone call each ported number to verify incoming calls work
• Test mobile data on each line
• Check that voicemail is set up correctly
• Verify any call diversion or forwarding rules are in place

Coordinating a Bulk Port: Tips for Larger Businesses

Porting 10, 20, or 50+ lines simultaneously requires careful planning:

Stagger the Ports if Possible

Rather than porting all lines on the same day, consider staggering them over 2-3 days. Port 5-10 lines per day. This way, if any issues arise with the first batch, you can resolve them before porting the rest.

Choose a Mid-Week Porting Day

Avoid porting on Mondays (busiest day for business calls) and Fridays (risk of issues carrying over into the weekend). Tuesday, Wednesday, or Thursday are ideal porting days.

Inform Your Team

Tell affected employees when the port is happening and what to expect. They should:

• Keep their old SIM in the phone until the new SIM activates (the old SIM will stop working automatically when the port completes)
• Have the new SIM ready to insert (or eSIM QR code ready to scan)
• Be prepared for a 2-4 hour window where their line may be in transition
• Have an alternative contact method (email, Teams, WhatsApp on WiFi) during the switchover

Appoint a Porting Coordinator

Designate one person (usually from IT or operations) to manage the porting process. They should have a master spreadsheet listing every line, its PAC code, the porting date, and confirmation of successful transfer.

Early Termination Fees: What to Expect

If any of your lines are still within their minimum contract term, you will face early termination fees (ETFs). Here is how each network typically calculates them:

When you request a PAC code, your current provider must tell you the exact ETF amount. Factor this into your cost comparison -- sometimes the savings on a new deal outweigh the ETF within a few months.

Tip Some new providers offer to buy out your remaining contract as an incentive. Ask about "switching credits" or "ETF contributions" when negotiating with new providers, especially if you are bringing 5+ lines.

What to Check Before You Switch

Run through this checklist before committing to a new provider:

• Coverage check: Verify 4G/5G coverage at your key locations (office, employee homes, regular travel routes) using each network's coverage checker
• Data allowances: Ensure the new plan provides enough data for each employee's actual usage
• Roaming: If your team travels, compare roaming charges between providers for your most common destinations
• Fleet management tools: Check that the new provider's business portal meets your needs for billing, spend controls, and line management
• Contract flexibility: Look for staggered refresh dates and the ability to upgrade or change plans mid-contract
• SIM type: Confirm whether you need physical SIMs or eSIMs, and whether the new provider supports your preference

STAC Codes: Switching Without Keeping Your Number

If you do not need to keep a particular phone number (for example, if you are replacing temporary or internal-only lines), you can use a STAC (Service Termination Authorisation Code) instead of a PAC code. Text "STAC" to 75075 to terminate your current contract without porting the number. Your old contract will end within 30 days.

How Long Does the Entire Process Take?

Here is a realistic timeline for switching a business account with 10 lines:

With proper planning, you can complete the entire switch in under two weeks, with actual service disruption limited to a few hours on porting day.