TL;DRConsumer lines default to dynamic addressing because it lets an ISP serve more subscribers with fewer addresses and keeps support simple. Getting a static one usually means a business-tier account, a higher monthly bill, a lead time measured in days, and availability that varies by area — and on CGNAT lines it may not be available at all.
Why dynamic is the default
Because it is cheaper for the ISP, in a way that has nothing to do with you. Addresses are a finite, purchased resource. Assigning them dynamically lets a provider serve more subscribers than it holds addresses, since not every line needs one simultaneously.
- Address economics: a pool shared across subscribers stretches a limited allocation much further than one address per household permanently.
- Support cost: a static assignment is a configuration that can be mismatched, and mismatches generate calls. Dynamic assignment self-heals.
- Product segmentation: static addressing is a business-tier feature, and moving it downmarket removes a reason to upgrade.
- Terms of service: many consumer agreements discourage or prohibit running reachable services, and static addressing is what makes that practical.
CGNAT: sometimes there is nothing to give you
On lines behind carrier-grade NAT, subscribers share a public address at the carrier level and no unique public address is assigned to your line at all. No configuration on your side changes that.
This matters before you shop: if your line is behind CGNAT, the question is not which static plan to buy but whether the carrier offers a path off CGNAT in your area at all. Some do, as a paid option; some do not.
What a static line actually costs to obtain
| Cost | What it looks like in practice |
|---|---|
| Account type | Usually a business-tier account rather than a consumer plan |
| Monthly premium | The static option is billed on top of the line, often as a block rather than a single address |
| Lead time | Provisioning is a carrier-side operation with a scheduled window, not an instant toggle |
| Availability | Varies by area and by plan; not every address a carrier serves can be made static |
| Fragility | A carrier-side change to the line can break your configuration without warning |
That last row is not hypothetical. A carrier technician converting our own lines from dynamic to static configuration is exactly what took our infrastructure offline in August 2026 — our equipment was still configured for the old scheme and dropped off as leases expired.
Doing it yourself versus buying it
Running your own line is a legitimate choice and sometimes the right one. It is worth being honest about what each side actually costs.
| Your own line | Buying a hosted instance | |
|---|---|---|
| Address control | Complete | Contractual — depends on the provider stating exclusivity |
| Monthly cost | The whole line, regardless of how many addresses you use | One address's share of a line |
| Physical presence | Required — the line terminates where you are | Not required |
| Recovery when it breaks | You go there | The provider's problem, if they have built for it |
| Address count | Whatever the carrier gives that line | One dedicated address per instance |
| Right when | You need presence in a place you already occupy, and you want no dependency on anyone | You need presence somewhere you are not, or you do not want to own the recovery problem |
The question to answer before deciding
Where does the address need to be? If the answer is somewhere you already live or work, running your own line is usually cheaper and always more controllable. If the answer is somewhere you are not, you are not really comparing costs — you are choosing between a provider and a plane ticket.
The second question is who absorbs an outage. On your own line that is you, on a weekday, in person. That is not an argument against doing it; it is the cost you should price in before you start.
Frequently Asked Questions
Why won't my ISP give me a static IP?
Mostly economics. Dynamic assignment lets a provider serve more subscribers than it holds addresses, keeps support simple, and preserves static addressing as a business-tier feature. Many consumer terms also discourage running reachable services.
What is CGNAT and how do I know if I'm behind it?
Carrier-grade NAT means subscribers share a public address at the carrier level, so your line has no unique public address. Compare the address your router reports on its WAN interface with the address the internet sees — if they differ and the WAN one is private, you are behind it.
Is it cheaper to get my own static line than to rent one?
Per address, often yes — if you need the address where you already are. You pay for the whole line regardless of how many addresses you use, and you absorb every outage in person. The comparison changes completely when you need presence somewhere you are not.
Can a static IP change without warning?
Yes, through carrier-side changes. In August 2026 a technician converting our lines' configuration took our own equipment offline because it was still set up for the previous scheme. Statically configured does not mean nobody upstream can alter it.
Updated 2026-08-25 · Back to Guides · View plans →