The AI Receptionist Overage Trap: How $29/Month Becomes $100+
Budget AI receptionists advertise entry prices of $24.95 to $29 per month, but overage fees quietly inflate the real cost to $60, $90, or over $100 once a business exceeds the included minutes or calls. As of June 2026, Dialzara's $29/month plan includes just 60 minutes and charges $0.48/minute after that, so a business using 200 minutes pays $96.20/month. AIRA's $24.95/month Starter plan covers only 30 calls and bills $1.50 per call thereafter, forcing any business with moderate volume onto a $159.95/month Pro plan. Trillet's AI receptionist ($49/month, 150 minutes included, $0.20/minute overage) costs $59 at 200 minutes and $99 at 400 minutes, making it the most predictable option once you factor in real usage. This article breaks down the actual monthly cost at four usage levels, explains why per-call and per-caller billing models hide the real number, and shows how to calculate your own bill before you sign up.
Trillet is not unlimited and it is not free past the line: every minute over the included 150 still costs $0.20. The argument here is not that Trillet has no overage. It is that $0.20/minute is the lowest published per-minute overage rate among major AI receptionist providers, and per-minute billing is the only model where you can predict the bill at all.
The Bottom Line
- A business using 200 minutes per month will pay between $59 (Trillet) and $96.20 (Dialzara), despite advertised prices clustering around $29 to $50
- Per-call and per-caller billing models (AIRA, UpFirst, Goodcall) make cost prediction nearly impossible because a 30-second call costs the same as a 10-minute booking call
- The cheapest advertised plan is almost never the cheapest plan at real-world usage levels
Which Trillet product is right for you? If you are a small business that needs an AI receptionist for missed calls, Trillet's D2C plan is $49/month with 150 minutes included and $0.20/minute overage. If you are an agency or reseller looking to offer AI receptionists to your own clients, Trillet's White-Label platform starts at $99/month with $0.12/minute usage costs.
Total Cost at Real Usage: The Numbers
Every AI receptionist provider structures pricing differently, which makes apples-to-apples comparison difficult by design. The table below normalizes cost to what you actually pay per month at four common usage levels. All pricing data is as of June 2026.
| Provider | Base Price | Included | Overage Rate | Cost at 100 min | Cost at 200 min | Cost at 300 min | Cost at 400 min |
|---|---|---|---|---|---|---|---|
| Dialzara | $29/mo | 60 min | $0.48/min | $48.20 | $96.20 | $144.20 | $192.20 |
| Phonely | $50/mo | 250 min | $0.25/min | $50 | $50 | $62.50 | $87.50 |
| AIRA | $24.95/mo | 30 calls | $1.50/call | ~$130* | ~$159.95** | ~$159.95** | ~$159.95** |
| Goodcall | $79/mo | 100 callers | $0.50/caller | $79 | ~$94*** | ~$104*** | ~$114*** |
| Trillet | $49/mo | 150 min | $0.20/min | $49 | $59 | $79 | $99 |
* AIRA uses per-call billing, not per-minute. 100 minutes is roughly 40 to 70 calls depending on average call duration. At ~50 calls, the Starter plan's 30-call cap is exceeded by 20 calls at $1.50 each, adding ~$30 to the $24.95 base, or roughly $55. At higher call counts the math pushes you onto the $59.95 Premium (90 calls) or $159.95 Pro (300 calls) plan, since stacking per-call overage quickly costs more than upgrading.
** AIRA's Starter (30 calls) and Premium (90 calls) plans cannot accommodate the call count behind 200 to 400 minutes of talk time. The Pro plan at $159.95/month covers 300 calls and is the realistic landing tier.
*** Goodcall bills $0.50 per unique caller above its plan cap, not per minute. A caller who phones ten times counts once, and call length is free, but a busy month with many first-time callers stacks $0.50 charges. The figures assume 30 to 70 unique callers over the 100-caller Starter cap; your number depends entirely on how many distinct people call.
Two things stand out. First, Dialzara's cost curve is the steepest in the market because $0.48/minute overage compounds fast. A business using 400 minutes pays $192.20, more than six times the advertised $29. Second, per-call and per-caller models (AIRA, Goodcall) snap to plan tiers rather than scaling smoothly, so a small increase in volume can trigger a large jump in the bill.
Trillet's cost curve is the flattest of the per-minute options. The combination of 150 included minutes and $0.20/minute overage means the jump from base price to 400 minutes of usage is $50 in overage, not $163 (Dialzara). Trillet still charges for those overage minutes. It simply charges the least per minute and lets you see exactly what each minute adds.
Per-Minute vs. Per-Call Billing: Why the Model Matters
Per-call billing, used by AIRA and UpFirst, charges the same rate whether a call lasts 20 seconds or 15 minutes. That pricing model creates three problems for small businesses.
Short calls burn the same budget as long ones. A spam call that slips through filtering, a wrong number, or a quick "what are your hours?" call costs the same as a detailed appointment booking. On AIRA's Starter plan (30 calls at $24.95/month, $1.50 per call after), each call effectively costs $1.50 regardless of length.
Volume prediction is harder. Most businesses can estimate total call minutes from phone records, but predicting the number of discrete calls is less intuitive. A business might field 80 calls in a slow month and 150 in a busy one, making per-call budgeting unreliable.
Average call duration shifts the math. If your average call is 2 minutes, AIRA's $1.50 per-call rate works out to $0.75/minute. If your average call is 5 minutes, the effective per-minute rate drops to $0.30. That kind of variance makes it difficult to project monthly costs accurately, and even the best case ($0.30/minute) is higher than Trillet's $0.20/minute overage. Goodcall's per-caller model has the same problem in a different shape: you cannot know in advance how many unique people will call.
Per-minute billing (Dialzara, Phonely, Trillet) is more transparent because the cost scales linearly with actual usage. A 2-minute call costs twice as much as a 1-minute call. The AI Receptionist Pricing Models Explained guide covers these billing structures in more detail, and the AI Receptionist Guide for Small Businesses explains how included minutes work alongside the per-minute rate.
What to Look for in AI Receptionist Pricing
Comparing AI receptionists on sticker price alone misses most of the real cost. Four variables determine what you actually pay each month: how many minutes or calls are included, the overage rate, whether the provider forces plan upgrades, and which features are gated behind higher tiers.
Included minutes (or calls) relative to your volume
A plan with 60 included minutes only works for businesses receiving fewer than 60 minutes of AI-handled calls per month. If your AI receptionist handles 15 calls a day averaging 2 minutes each, that is roughly 900 minutes per month. The "included" allocation on most budget plans covers less than a week of that volume.
Overage rate
This is the single most important number in any AI receptionist pricing page. As of June 2026, Dialzara charges $0.48/minute, Phonely charges $0.25/minute, and Trillet charges $0.20/minute. At 250 minutes of overage, those rates produce overage costs of $120, $62.50, and $50 respectively, a $70 spread on the same usage. The AI Phone Answering Service Cost Breakdown walks through overage math across more providers.
Forced plan upgrades
Some providers structure pricing so that exceeding your allocation means jumping to the next plan tier rather than paying a smooth per-minute rate. AIRA's per-call tiers (30, 90, then 300 calls) and Goodcall's per-caller caps both create step changes: once you cross a threshold, the cheapest path is often to upgrade the whole plan. Per-minute providers that publish a flat overage rate, like Trillet at $0.20/minute, let you pay only for what you use above the line instead of buying the next bucket.
Feature gating behind higher tiers
Price is not the only thing that changes when you upgrade. Several budget providers lock appointment booking, CRM integration, or compliance to higher tiers. Trillet includes calendar integration, SMS follow-up, and spam blocking on its $49/month plan with no feature gating. Verify which features are bundled before comparing base prices, because a cheaper plan that excludes booking is not actually cheaper for a business that needs booking.
When "Cheap" Becomes Expensive
The overage trap works because small businesses tend to sign up based on current call volume and then discover their AI receptionist handles more calls than expected. That is actually the point of the product: it catches missed calls you were not answering before. The calls that the AI now handles are calls that previously went to voicemail or were lost entirely.
A plumber who currently misses 10 calls a week might estimate 40 calls per month, averaging 3 minutes each, for 120 minutes. On Dialzara's $29/month plan (60 minutes included), that works out to $29 + (60 x $0.48) = $57.80. Not terrible. But when word of mouth picks up during summer, call volume doubles. At 240 minutes, the bill becomes $29 + (180 x $0.48) = $115.40.
On Trillet, the same plumber pays $49 at 120 minutes (within the 150-minute allocation) and $49 + (90 x $0.20) = $67 at 240 minutes. Trillet still bills for those 90 overage minutes, but the gap between the two providers widens as volume increases, not narrows, because Trillet's per-minute rate is lower and its included allocation is larger.
Industry pricing roundups reach the same conclusion. A June 2026 comparison from Aira's own pricing guide and a separate 10-vendor cost analysis from Ainora both note that low entry prices are routinely offset by steep per-minute or per-call overage, which is the mechanism described here. The providers with the cheapest advertised prices are often the most expensive at real-world usage precisely because their business model depends on overage revenue. Low base prices attract signups. High overage rates generate margin. The sticker price is not the price.
How to Calculate Your Real Monthly Cost
Estimating your actual AI receptionist cost requires three numbers: your monthly call volume, average call duration, and the provider's overage structure. Here is how to find those numbers if you do not already have them.
Check your phone's call log or carrier dashboard for the past 3 months. Count incoming calls only (not outgoing). Multiply by average call duration. Most small business calls average 2 to 4 minutes.
Then apply the formula: Base plan price + ((Total minutes used - Included minutes) x Overage rate) = Actual monthly cost.
For per-call providers like AIRA, the formula changes to: Base plan price + ((Total calls - Included calls) x Per-call overage rate). AIRA bills $1.50 per call over the cap, but because stacking per-call charges quickly exceeds the next plan's price, you should also check whether upgrading the tier is cheaper at your volume. Goodcall's per-caller model uses the same structure with unique callers in place of calls.
If your projected usage consistently exceeds 300 minutes, compare the mid-tier plans directly rather than assuming the cheapest entry plan will save money. A $49 plan at 400 minutes of usage will always cost less than a $29 plan at the same volume when the overage differential is $0.28 per minute.
Frequently Asked Questions
Which AI receptionist has the lowest overage rate?
Trillet charges $0.20/minute in overage, the lowest published per-minute rate among major AI receptionist providers as of June 2026. Phonely charges $0.25/minute on its Starter plan, and Dialzara charges $0.48/minute. AIRA and UpFirst use per-call billing (AIRA at $1.50/call) and Goodcall bills $0.50 per unique caller, which makes direct per-minute comparison difficult.
Does Trillet have overage charges, or is it unlimited?
Trillet has overage charges. The $49/month plan includes 150 minutes, and every minute beyond that costs $0.20. It is not unlimited and it is not free past the included allocation. The advantage is that $0.20/minute is the lowest published per-minute overage rate and there is no forced plan upgrade, so you can predict the bill exactly.
Why do AI receptionist plans include so few minutes?
Low included-minute allocations keep the advertised price low, which drives signups. Dialzara's $29/month plan includes only 60 minutes because that price point attracts budget-conscious buyers. The overage rate ($0.48/minute) is where the provider generates most of its revenue from active users. This is a standard SaaS pricing tactic, not unique to voice AI.
Is per-call or per-minute billing better for small businesses?
Per-minute billing is more predictable for most small businesses because costs scale linearly with actual phone time. Per-call billing (AIRA, UpFirst) charges the same amount for a 30-second call and a 10-minute call, and per-caller billing (Goodcall) charges per distinct phone number regardless of call length. Both make budgeting harder. If your business receives many short calls, per-call and per-caller billing penalize you.
How many minutes does a typical small business use per month?
Small businesses that use an AI receptionist as backup for missed calls typically use 100 to 300 minutes per month, depending on industry and call volume. Service businesses like plumbers, HVAC, and electricians tend toward the higher end (200 to 400+ minutes) because their calls involve scheduling, job scoping, and emergency triage. Professional services like law firms and accountants often land at 100 to 200 minutes.
Does Trillet charge overage automatically or require a plan upgrade?
Trillet charges overage at $0.20/minute with no forced plan upgrade. If you use 200 minutes on the $49/month plan (150 minutes included), your bill is $59. There is no service interruption, no tier jump, and no surprise. You pay for what you use above the included allocation, at a flat and published rate.
Updated for June 2026: Refreshed all competitor overage rates to current published values (Dialzara $0.48/min, Phonely $0.25/min, AIRA $1.50/call, Goodcall $0.50/unique caller), re-derived every cost example, added a Goodcall per-caller row, added third-party pricing citations, and clarified that Trillet has overage at $0.20/minute rather than implying it is unlimited.