The U.S. wireless industry supports three distinct types of phone numbers for A2P messaging: 10DLC long codes, short codes, and toll-free numbers. Each has its own use cases, regulatory framework, throughput characteristics, and price points. Choosing the right one for a given messaging program is one of the more consequential decisions a Brand makes. This section walks through what each option is, what it is good for, what it is not good for, and how to think about choosing.

The quick comparison

Before we get into details, here is the at-a-glance comparison:

Each of these formats fits a different use case, and the right answer depends on what you are trying to accomplish.

10DLC: the new default

10DLC is now the default option for most business messaging. This is what the bulk of this Knowledge Center is about. The key features:

A 10-digit phone number that looks like a normal phone number to the consumer. Local area codes are available, which can be useful for businesses that want to look like a local presence.

Tier-based throughput depending on Brand vetting and use case. Top-tier brands can support meaningful per-minute and daily volumes. New or unvetted brands start at lower tiers until they vet up.

Voice and SMS on the same number. A 10DLC number can be used for both inbound voice calls and SMS messaging. This is one of 10DLC's main advantages over short codes. Your customer can call the same number they are texting from.

Modest cost structure. Setup is a small fee per Brand registration, plus monthly campaign fees that vary by use case, plus per-message termination fees. The ongoing cost for most use cases is dramatically lower than short codes.

Days-to-weeks setup time. A clean registration with a Standard use case can be live within a few business days. Special use cases or complex registrations can take weeks.

Best for: Most business messaging needs. Customer notifications, marketing campaigns, transactional alerts, two-factor authentication, customer service interactions. If you are starting a new messaging program in 2026 and you do not have specific reasons to choose otherwise, start with 10DLC.

Not great for: Extremely high-volume bursts (where short codes still hold the throughput advantage), brand-recognizable shortcuts (a memorable 5-digit number is easier to remember than a 10-digit number), and certain high-end consumer messaging programs where the brand wants the prestige of a short code.

Short codes: high volume, high cost, high prestige

Short codes are 5- or 6-digit phone numbers used primarily for high-volume A2P messaging. They predate 10DLC and remain a meaningful part of the messaging landscape.

A 5- or 6-digit number that is nationally routed (not tied to a geographic area code). Vanity short codes (specific numbers chosen for memorability or brand alignment) cost more than randomly-assigned ones.

The highest throughput available. Short codes can sustain higher per-second message rates than even top-tier 10DLC. For consumer-facing messaging at large scale, short codes still have a throughput advantage.

SMS only. Short codes do not support voice. If your consumer calls back the short code, the call does not connect. This is a common source of consumer confusion.

MMS support. Short codes support MMS, which is important for brands that send images, videos, or rich content.

High setup costs and timelines. Setting up a short code involves applying through a different registration body (the Short Code Registry), getting approval from each carrier independently for the specific use case, and waiting through carrier review queues that can take months. Setup costs include short code lease fees and additional fees for vanity numbers.

Recurring monthly costs are substantial, plus per-message termination fees. The total cost of ownership is dramatically higher than 10DLC.

Best for: Established brands with very high messaging volume, where the throughput and brand recognition justify the cost. Examples: large national retailers' loyalty programs, major financial institutions' high-volume notifications, election-day political turnout operations. Also still the right choice for SMS marketing programs where consumers are expected to text the short code as part of the call to action ("Text JOIN to 22000").

Not great for: New messaging programs, low-to-moderate volume use cases, businesses that need voice on the same number, or any program where the cost-to-volume ratio does not justify the high recurring fees. Most small and mid-sized businesses do not benefit from short codes. They should be on 10DLC.

Toll-free: the often-forgotten option

Toll-free numbers, which are numbers in the 800, 888, 877, 866, 855, 844, and 833 prefixes, have their own A2P messaging framework, separate from 10DLC and short codes.

An 8-digit toll-free number that is nationally recognized. Voice and SMS can both run on the same number.

Moderate throughput. Toll-free messaging has its own throughput model, with rules registered through the toll-free aggregators. Throughput is generally lower than top-tier 10DLC and dramatically lower than short codes.

Voice + SMS on the same number. Same advantage as 10DLC. A consumer can call your toll-free number for support and receive text confirmations on the same number.

Modest cost structure comparable to 10DLC.

Days-to-weeks setup time with a registration process that is similar in concept to 10DLC's TCR registration but uses different infrastructure (Somos and the toll-free aggregators).

Best for: Customer service-oriented messaging, transactional confirmations, programs where the toll-free voice number is already in use and adding messaging is a natural extension. Brands that have an established 1-800 customer service line often find that adding messaging on the same number is a cleaner consumer experience than spinning up a separate 10DLC for messaging.

Not great for: Very high-volume marketing (10DLC or short codes are better at scale), local-presence use cases (the 800-series is explicitly non-local), and most consumer-facing marketing where local-area-code 10DLC numbers feel more personal.

How to choose

A few decision frames that help:

"I am starting a new messaging program from scratch."

Start with 10DLC. It is the cheapest, fastest, and most flexible option. If you discover later that you need short code throughput or want toll-free's voice integration, you can add or migrate. The default starting point in 2026 is 10DLC.

"I have an existing 1-800 customer service number."

Strongly consider toll-free messaging. The consumer experience of calling and texting the same number is good, and the operational simplicity of managing one number for two channels is real. Toll-free messaging is often underutilized for this use case.

"I am running a high-volume marketing program."

Compare top-tier 10DLC against short code. For most brands, top-tier 10DLC provides enough throughput. For the largest brands with the highest volumes, short codes still hold the per-minute throughput advantage.

"I want consumers to text a memorable number."

Short codes are the only option here. A 5-digit number is easier to remember and put on a billboard than a 10-digit number. The cost is real but for some use cases the brand recognition justifies it.

"I need both voice and messaging on the same number."

10DLC or toll-free. Short codes do not support voice.

"My audience is geographically concentrated and I want a local presence."

10DLC with a local area code. Short codes are national-only. Toll-free is national-only.

"I am a sole proprietor or very small business."

10DLC, with the Sole Proprietor use case if you do not have an EIN. Short codes are economically infeasible at small scale.

"I am running a political campaign."

10DLC with the Political use case, or short code if the campaign is large enough to justify it. Both are common in political messaging.

What changed with 10DLC

For context, the rise of 10DLC over the last several years has shifted the landscape significantly:

Pre-10DLC era. Most A2P messaging used either short codes (for high-volume programs) or unsanctioned long codes (for everything else). The unsanctioned long code traffic existed in a regulatory grey zone, tolerated but not officially sanctioned, with throughput and reliability issues.

Early 10DLC era. 10DLC was rolled out as the sanctioned alternative to grey-zone long code messaging. Adoption was slow at first as the registration infrastructure was built and the carriers worked out enforcement.

Mature 10DLC era (2023 to present). Most legitimate A2P messaging from 10-digit numbers now flows through registered 10DLC. The carriers and aggregators have phased out unregistered traffic. Short codes remain valuable for the highest-volume programs, but their share of total A2P traffic has declined as 10DLC has become viable for use cases that previously required short codes.

The future. RCS Business Messaging is starting to arrive and may eventually reshape the landscape again. AI-driven conversational commerce will create messaging patterns that do not fit cleanly into any of the current categories. The answer to "what number type should I use" may look different in five years. For now, 10DLC is the right default for most use cases, with short codes and toll-free filling specific niches.

The honest summary

The right number type depends on your use case, volume, budget, and brand requirements. There is no universal best answer.

For most businesses starting a messaging program today: 10DLC. For very high-volume brand-recognized programs: short code. For programs where voice and messaging share a number and the toll-free brand is established: toll-free.

The mistake to avoid is choosing based on what was right five years ago. Five years ago, short codes were the default for serious A2P messaging because 10DLC did not really exist yet. That is no longer true. If you are carrying a legacy short code that no longer makes economic sense for your current volume, look hard at whether a 10DLC migration could meet your needs at a fraction of the cost.

RELATED SECTIONS

• What is 10DLC, Really?

• The 10DLC Ecosystem: Who Does What