The single most common self-inflicted 10DLC problem I see isn't a rejection. It's a sender who got approved — cleanly, first try — and then watched their delivery quietly sag two weeks later, wondering what broke. Nothing broke. They registered the wrong use-case, and the carriers are now throttling them exactly as designed.
Full disclosure: I work for Ready, an SMS platform that handles 10DLC registration in-app. So I've watched a lot of these forms get filled out, and the use-case field is where good senders trip. It looks like a dropdown. It's actually a contract with the carriers about what you'll send — and if your actual message mix doesn't match the box you ticked, you get filtered, capped, or both.
Here's how to pick the one that matches reality.
What the use-case field actually controls
When you register a 10DLC campaign, you're telling the carriers three things at once:
- The category of your traffic (marketing, transactional, mixed, etc.)
- The consent model they should expect behind it
- The throughput and trust profile they'll assign you
That third one is the sneaky part. Carriers — T-Mobile especially — assign per-second and per-day send limits partly based on use-case. A pure marketing campaign gets treated with more suspicion than an account update or an OTP. If you file "Marketing" but 95% of what you send is appointment reminders, you've volunteered for the stricter throttle and set an expectation your message content contradicts.
For the mechanics of how the same registration behaves differently across carriers, same campaign, different carriers walks through why AT&T waves things through that T-Mobile crawls.
The four use-cases most senders are choosing between
Ignore the long list of specialized categories (2FA, security alerts, public service) unless you're one of those things specifically. For the vast majority of businesses, the real decision is among these four:
| Use-case | What it's for | Consent expectation | Throughput profile |
|---|---|---|---|
| Low Volume Mixed | Small senders, any mix of promo + transactional | Standard opt-in | Lowest caps, easiest approval |
| Mixed | Both marketing and transactional from one number | Opt-in required for the promo portion | Moderate |
| Marketing | Promotions, offers, sales, newsletters | Explicit marketing opt-in | Stricter carrier scrutiny |
| Conversational / Customer Care | Two-way, human-driven back-and-forth | Contact initiated or has active relationship | Favorable if genuinely 2-way |
The names are close enough to feel interchangeable. They aren't. Pick by looking at what actually leaves your account in a normal week.
Do the message-mix audit first (it takes 20 minutes)
Before you touch the dropdown, list every automated and manual message you'll send and tag each one:
- Reminders, confirmations, receipts, shipping updates, OTPs → transactional
- Sales, offers, "we miss you," newsletters, re-engagement → marketing
- Replies to inbound questions, human conversations → conversational
Now count. If it's:
- 90%+ transactional, occasional promo → you likely want Mixed, not Marketing. Filing Marketing here is the classic mistake — see why registering marketing for transactional texts drops your delivery.
- Mostly promotional blasts → Marketing is correct. Own it.
- A real mix, and you're under a few thousand messages a month → Low Volume Mixed is the pragmatic choice.
- Genuinely two-way, someone-texts-you-first → Conversational, but only if that's honestly true.
The audit matters because the sample messages you submit have to match your declared use-case. If you file Marketing and your samples are all "Your appointment is confirmed for 2pm," a careful reviewer bounces it — and if they don't, the carrier filters catch the mismatch later.
The reminder trap, specifically
The title of this post exists because reminders are where the most senders guess wrong. A dentist, a salon, a fitness studio, a repair shop — their SMS is 80% "you're booked Thursday at 3" and 20% "we have a cancellation, want it?"
Instinct says "we're marketing our business, so… Marketing?" Wrong instinct. Reminders are transactional. Confirmations are transactional. Cancellation-fill offers to an existing customer with an active relationship lean transactional too. Filing Mixed covers the whole spread and keeps you out of the marketing throttle for the 80% of traffic that shouldn't be there.
Healthcare senders have an extra wrinkle here: a reminder and a "book your flu shot" promo actually sit on opposite sides of the consent wall, which affects both your use-case and your opt-in language. Same principle — the message decides the category, not the business.
When Conversational is the right call (and when it's a trap)
Conversational / Customer Care use-cases can get favorable treatment because carriers like genuine two-way traffic — a human replying to a human. But there's a definition test: conversational means the contact initiated or there's an active back-and-forth, roughly one outbound per inbound.
If you're firing 5,000-message blasts and calling it conversational because a few people reply, you've mislabeled a broadcast. Carriers detect the one-to-many pattern and treat it as marketing anyway — now you're throttled and flagged for a mismatch. File Conversational only if your inbox genuinely looks like conversations.
Nonprofits hit a version of this constantly: peer-to-peer donor texts and broadcast appeals are two different use-cases, and filing one for both throttles both.
What a mismatch actually costs
Let's put numbers on it, because "throttled" is abstract until it hits a send window.
Say you register Marketing with a standard trust score, and T-Mobile hands you a conservative daily cap — pick a round number, 2,000 segments/day to that carrier. You've got 6,000 T-Mobile contacts and you want a same-day reminder blast out by lunch. At a 2,000/day cap, that send takes three days to fully deliver. Your Wednesday reminders reach a third of the list on Friday — useless.
File Mixed (or Low Volume Mixed) with matching transactional samples and that same account often clears a materially higher daily allowance, because the traffic profile reads as lower-risk. Same messages, same contacts, same number — different box ticked, and the send actually lands the day you send it.
The cost isn't a fee. It's undelivered messages during the window they mattered, which for reminders is the entire point of the message.
Getting it registered without a three-week detour
The good news: fixing this is cheap and fast if your platform does self-serve registration. In Ready, you file brand and campaign registration in-app — roughly ~$10/mo per brand and ~$20/mo per campaign in carrier fees — pick the use-case that matches your audit, submit matching sample messages, and most approvals land same-day, with the full range typically 1–3 days. No emailing a support queue for two weeks to get a form re-keyed.
If you do get bounced, don't guess at the resubmit. The two most common rejection reasons are use-case mismatch and SHAFT/content flags — both have specific rewrites that clear them. And if you're a GHL agency spinning up clients, the same-day 10DLC path vs the three-week onboarding trap covers how to get a client texting this week without cutting corners.
A note on brand vetting: you'll see a $40 (or $100 enhanced) optional vetting upgrade that raises your trust score and daily caps. It's real and sometimes worth it — but it's a throughput lever, not a fix for a wrong use-case. Vetting a mislabeled campaign just lets you send the wrong-category traffic faster into the same filters. Match the use-case first; consider whether vetting earns its $40 second.
The practical takeaway
The use-case field isn't a description of your business — it's a description of your traffic. So do the audit before the dropdown:
- Tag every message you send as transactional, marketing, or conversational.
- Reminders, confirmations, and receipts are transactional — file Mixed, not Marketing, if that's most of your volume.
- File Marketing only when promo blasts genuinely dominate, and own the stricter caps.
- File Conversational only if your inbox is actually two-way.
- Make your sample messages match the box you tick — that's what reviewers and carrier filters check.
Get this right once and you never think about it again. Get it wrong and you'll spend months blaming deliverability gremlins that are really just a carrier honoring the throttle you signed up for.
If you want to set it up cleanly from the start, you can register on the right use-case inside Ready and start with 2,500 free credits — no card required — to test your sample messages against real sends before you scale.