How to switch providers without downtime
How long each stage of a switch takes, the order to do them in, why ports get rejected, and what else has to move with the service.
Why run both services at once?
Run both services at once for a short period. Order the new circuit, let it be installed and tested, port your numbers over roughly 5 to 14 business days, then disconnect the old service. Paying for two connections for a few weeks is the entire cost of not being offline.
How long to allow
| Stage | Typical time | Notes |
|---|---|---|
| Order to install survey | 1–2 weeks | Longer if the building needs a site visit or landlord access |
| Standard install, existing facilities | 2–4 weeks | Where the provider already has a route into the building |
| Install requiring construction | 60–90 business days | Permits and street work. Can run longer, and often does |
| Testing and overlap | 1–2 weeks | Enough to see a full business cycle, including a busy day |
| Number porting | 5–14 business days | Complex or multi-line ports take longer |
| Old service disconnection | After everything above | Subject to your notice period on the old contract |
The order of operations
Confirm the new service is available at the exact address
Serviceability is per building, sometimes per suite. Get it confirmed against your full address before anything else.
Order the new service, and keep the old one running
Do not give notice on the old contract yet beyond preserving your non-renewal deadline.
Let the install complete and test properly
Speed both ways, a full business day of real use, and anything that depends on a static address or firewall rule.
Submit the port with exact details
The letter of authorization must match the losing carrier records exactly. Check it against the rejection reasons in "Why ports get rejected" first.
Cut traffic over gradually
Move a few users or one line first, then the rest once it is stable.
Confirm the port completed, then disconnect
Only after every number is confirmed live on the new carrier. Then send notice in the form your old contract requires.
Why ports get rejected
- The business name on the letter of authorization does not match the losing carrier record exactly, including punctuation and suffixes like Inc or LLC
- The service address on file differs from the one you submitted, often an old suite number
- The account number or PIN is wrong, or the account has a port freeze on it
- Some of the numbers listed are not actually on that account, or are not portable
- The account has a past-due balance
- The signer is not the authorized contact of record
Every one of these is fixable before you submit. Ask your current provider for a customer service record showing exactly how your account is stored, and copy from it word for word rather than from your letterhead.
What else to line up
- Static IP addresses, if anything points at your current ones — DNS, a VPN, a card terminal, a remote-access rule
- Firewall and router configuration, and who will move it
- Alarm panels, elevator lines and fax lines, which are easy to forget and hard to restore
- E911 registration for the new service address
- Equipment return for the old provider, including deadlines and shipping evidence
If the timing does not work
When the new install will land after your notice deadline, give non-renewal notice to protect the option and ask the old provider for a short month-to-month extension. That usually costs more per month than the term rate, and far less than being between two services. If neither is possible, renewing and switching at the next term end is a legitimate answer.
Install timelines, porting rules and notice requirements vary by provider and by address. Your own signed agreements on both sides govern.
Last reviewed September 14, 2026
