Short Code, Long Code or Toll-Free for District Texting
Every comparison of these options currently online was written by a company that resells one of them. The buyer-side question is narrower than the vendor-side one and has a number attached: how long does it take to reach twelve thousand families at 05:15, and does a parent recognise who is texting them.
| Dimension | Short code | 10DLC long code | Toll-free |
|---|---|---|---|
| Typical throughput | Very high — hundreds/sec | Tiered, tens/sec typical | Moderate |
| 12,000-family blast, 1 segment each | Under 1 minute | 3–20 minutes | 5–25 minutes |
| Monthly cost | Highest by an order of magnitude | Low | Low |
| Setup lead time | 8–12 weeks typical | 2–6 weeks | 1–3 weeks verification |
| Carrier filtering exposure | Lowest | Real if mis-registered | Moderate |
| Two-way replies | Yes | Yes | Yes |
| Portability if you change vendor | Possible, slow, contested | Generally portable | Varies |
| Parent recognition | Memorable but anonymous | Looks like a local number | Reads as a call centre |
| Per-school identity possible | One code, one district | A number per school if you want it | Possible, rarely worth it |
Most US districts land on 10DLC long codes, and for most districts that is correct. The two conditions that genuinely justify a short code are a very large enrolment where blast completion time is a stated requirement in the emergency operations plan, and a district whose long-code traffic has repeatedly been filtered despite correct registration.
Blast completion, worked properly
Completion time is the only number a superintendent actually asks about, and it is almost never quoted with the segment inflation included. Take 12,000 contact points, 35% receiving accented Spanish at three segments:
- Segments to send: 7,800 English + (4,200 × 3) = 20,400.
- Short code at 200 segments/sec: 102 seconds.
- Long code at 60/sec: 5 minutes 40 seconds.
- Long code at 10/sec: 34 minutes.
- Long code at 1/sec: 5 hours 40 minutes. This is what an unregistered or badly-tiered district is actually experiencing, and it is why the complaint arrives as "some parents got it and some didn't".
Write your requirement as a completion time, not as a throughput figure: "every family receives a district-wide emergency message within five minutes of send, including Spanish segment inflation" is a testable requirement that a vendor can be held to. "High throughput" is not.
Voice is a separate and much slower channel. Concurrent call capacity, not messages per second, governs it, and a 12,000-household voice blast at a few hundred concurrent lines takes tens of minutes regardless of what your SMS does. This is the practical reason to send SMS first and use voice as failover rather than as a parallel leg.
One number, or a number per school
A K-12-specific decision that generic guides never raise, and it changes front-office workload more than it changes anything technical.
One district number. Simpler registration, one campaign fee, one number for families to save, and every reply lands in one place. The cost is that replies land in one place: a district-wide closure message generates a wave of inbound texts that somebody in the central office has to triage and route, and most districts have not staffed for that.
A number per school. Replies land at the building, which is where the answer usually is. Families learn one number that means their child's school. The costs are real: more campaigns to register and pay for monthly, more numbers to keep warm, more places for a message to go unanswered over a school holiday, and a genuine risk that families receive district-wide messages from a number they have never seen.
The hybrid most districts converge on: one district number for district-wide and emergency traffic, and per-school numbers only for buildings that genuinely run two-way conversations with families. Do not create a number for a school that will not staff replies to it. An unanswered reply is worse than no reply channel.
Changing the number without losing the parents
Number changes are where districts lose reach, and it happens quietly. Families do not know the number changed; they only know that the messages stopped, or that an unknown number is texting them about their child, which reads as a scam.
A migration that works:
- Four weeks out: send from the old number, telling families the number will change on a date and what the new number is. Ask them to save it.
- Two weeks out: repeat, and include the new number in every email footer, the newsletter and the registration portal.
- Day one: send from the new number with a first line that identifies the district before it says anything else, and say explicitly that this is the new number families were told about.
- Days one to fourteen: keep the old number active and send a short forwarding message from it if anyone texts in.
- Week three: run a delivery-failure report against the new number and compare it to the last comparable send from the old one. A jump in failures is a data problem, not a number problem, and it was there before.
The first message from a new number must open with the district name. Families do not save numbers; they recognise senders by the first six words.
What Kastr does and does not do here. Kastr is not your carrier and does not sell you a number; the number type is a decision you make with your carrier or your platform's carrier relationship, and Kastr's own 10DLC registration is not complete — we do not hold a registration and will not tell you otherwise. What is built and relevant: SMS-to-voice failover on terminal failure with the two delivery records linked, so a filtered or failed text on any number type becomes a phone call rather than silence; row-level idempotency keyed on broadcast, person and channel, so a retry after a throughput throttle does not double-send; and a delivery queue that claims work with SKIP LOCKED and a five-minute claim TTL, so a worker that dies mid-blast recovers its rows rather than stranding them.
Questions people actually ask
Should a school district use a short code or a 10DLC long code?
A long code for most districts: far cheaper, faster to set up, portable, and it looks like a local number to a parent. A short code earns its cost in two situations — a very large enrolment where blast completion time is a written requirement, or a district whose correctly registered long-code traffic is still being filtered.
How long does it take to send a text message to 12,000 families?
Between about ninety seconds and several hours, depending entirely on throughput tier — and the honest calculation counts segments rather than messages, because accented Spanish messages are three segments each. Write your requirement as a completion time including segment inflation, then make the vendor demonstrate it.
Is a toll-free number good enough for school notifications?
Technically usually yes, with verification. The problem is recognition: a toll-free number reads to most parents as a call centre or a scam, and school messaging depends on the family opening it in the first eight seconds. If you use one, the district identifier at the start of every message is not optional.
Should each school have its own texting number or should the district share one?
Give a school its own number only if that school will staff replies to it. The reply volume, not the send volume, is what determines whether per-school numbers help. A common landing point is one district number for district-wide and emergency traffic plus per-school numbers for the buildings that genuinely run two-way conversations.
What happens to families when a district changes its texting number?
Reach drops, quietly, unless you run a migration. Announce the change from the old number four weeks and two weeks ahead, open the first message from the new number with the district name, keep the old number live for a fortnight with a forwarding reply, and compare delivery failure rates before and after.
One price. Every feature. Locked for three years.
$3.50 per student per year under 5,000 students. No tiers, no add-on modules, no per-message fees. Published on the site because you should not have to book a call to learn a price.