The scores
Each service is scored on its entry plan, the cheapest plan it publishes, so every vendor is judged on the same footing. Maximum score is 10.
For KaiCalls that is Kai Backup ($10, ~20 calls), which fits a business that needs overflow or after-hours cover. Above about 20 calls a month, the KaiCalls plan to buy is Kai Line ($79, ~170 calls), which scores the same 9/10: 2, 2, 2, 2, 1.
| # | Service (entry plan) | Calls per $ | Overage | Booking | Flat per call | Human fallback | Total |
|---|---|---|---|---|---|---|---|
| 1 | KaiCalls (Kai Backup, $10) | 2 | 2 | 2 | 2 | 1 | 9/10 |
| 2 | Upfirst (Starter, $24.95) | 1 | 0 | 2 | 2 | 1 | 6/10 |
| 2 | Goodcall (Starter, $79) | 1 | 1 | 1 | 2 | 1 | 6/10 |
| 2 | My AI Front Desk (Business-in-a-Box, $99) | 1 | 1 | 2 | 1 | 1 | 6/10 |
| 5 | Smith.ai (Starter, $300) | 0 | 0 | 1 | 2 | 2 | 5/10 |
| 6 | Dialzara (Business Lite, $29) | 1 | 1 | 0 | 1 | 1 | 4/10 |
| 6 | Abby Connect (Starter, $165) | 0 | 0 | 1 | 1 | 2 | 4/10 |
| 6 | Ruby ($250) | 0 | 0 | 1 | 1 | 2 | 4/10 |
| 9 | Rosie (Professional, $49) | 2 | 0 | 0 | 1 | 0 | 3/10 |
| 10 | AnswerConnect (price not published) | 0 | 0 | 0 | 0 | 2 | 2/10 |
Scores use only what each vendor's own pricing page showed on 10 Oct 2026. Sources are listed in the evidence table below. Calls per dollar, by our arithmetic: KaiCalls about 50¢ a call, Upfirst about 83¢, Goodcall 79¢ a customer, My AI Front Desk about 99¢, Dialzara about 97¢, Rosie about 39¢, and $3 or more for Abby Connect, Ruby and Smith.ai. A different weighting would give a different order, so the raw facts are there for you to re-score.
Scoring rules
Each criterion scores 0, 1 or 2, for a maximum of 10. Where a source didn't show a fact, the rule says how it scores.
- Calls per dollar (the plan compared, billed monthly): 2 = $0.50 or less per included call. 1 = $0.51 to $1.00. 0 = more than $1.00, or no published allowance. Minute-based plans are converted at 2 minutes per call (100 calls is roughly 200 minutes); that is our simplifying assumption to compare call-based and minute-based plans, not a measured average. Plans counted in unique customers are scored per customer.
- No overage charge: 2 = no per-call, per-customer or per-minute charge past the plan's allowance. 1 = a published overage of $1.00 or less per extra call or customer, or $0.50 or less per extra minute. 0 = a higher overage, or no overage rate in the sources we checked.
- Booking included: 2 = the plan books appointments on your calendar at no extra charge. 1 = a paid add-on, or available but not itemized for that plan. 0 = not on the plan, or not published.
- Flat price, whatever the call length: 2 = the allowance counts calls or customers, so a long call costs no more than a short one. 1 = the allowance counts minutes. 0 = no published allowance.
- Human fallback: 2 = live human receptionists answer. 1 = the AI can transfer callers to your own team on that plan. 0 = no transfer on that plan.
Why these rules. We revised the rules on 10 Oct 2026, and KaiCalls publishes this site. They weight what a small business pays per answered call and whether the bill can climb, which is where KaiCalls is strongest. They don't score published setup time, free trials, languages or channels beyond the phone, and the comparison below says where each vendor does better on those. Every fact is sourced, so you can re-score with your own weights.
The evidence behind each score
| Service | Entry plan | Over the allowance | Booking | Setup | Human fallback | Source |
|---|---|---|---|---|---|---|
| KaiCalls | Kai Backup $10/mo, ~20 Kai-answered calls/mo. Also Kai Line $79 (~170 calls) and Kai Office $349 (~800 calls). No per-minute overage | No overage charge; if volume stays higher, KaiCalls recommends the next plan and you can decline | Every plan, via a connected Google Calendar or GoHighLevel calendar | Self-serve; no setup fee; no go-live time published | Live call transfer and team routing on every plan; no human receptionists | kaicalls.com/pricing and kaicalls.com/backup, checked 2026-10-10 |
| Upfirst | Starter $24.95/mo, 30 calls, $1.50 per extra call | $1.50 per extra call on Starter | Every plan (Google, Outlook, Calendly and others) | Trains from your website, free 30-minute onboarding call; no go-live time published | Live, warm call transfers on every plan | upfirst.ai/pricing, checked 2026-10-10 |
| Rosie | Professional $49/mo, 250 minutes | No overage rate in the sources we checked | Sends appointment links by text; calendar booking from $149 Scale | Learns from your Google profile and website; no go-live time published | Transfers start on $149 Scale | heyrosie.com/pricing, checked 2026-10-10 |
| Goodcall | Starter $79/mo, 100 unique customers (about 150 calls by Goodcall's estimate), then 79¢ each | 79¢ per extra unique customer on Starter | Not itemized per tier; page describes a "booker" worker | Free demo agent you build yourself; no go-live time published | Page says you choose who receives transfers | goodcall.com/pricing, checked 2026-10-10 |
| Dialzara | Business Lite $29/mo, 60 minutes, $0.48/min after | $0.48 per extra minute | No calendar sync until $99 Business Pro | "Most customers go live the same day" | Blind transfer on Lite; warm transfer from Pro | dialzara.com/pricing, checked 2026-10-10 |
| My AI Front Desk | Business-in-a-Box $99/mo ($79 billed annually), 200 voice minutes | 25 credits ($0.25) per extra voice minute; auto-reload $10 per 1,000 credits (details) | Books the appointment; calendars connect through Zapier | "Setup in 5 minutes"; "Go live in under 5 minutes" | Call transfer is one of the plan's agent actions | myaifrontdesk.com/pricing, checked 2026-10-10 |
| Smith.ai | Starter $300/mo, 30 calls, $11.50 per extra call | $11.50 per extra call | $1.50 per booking add-on | Smith.ai onboards you; no go-live time published | Live receptionists, AI-first or human-first; 1 free transfer destination | smith.ai/pricing/receptionists, checked 2026-10-10 |
| Ruby | $250/mo, 50 receptionist minutes | Rate for minutes over your plan not published | Listed as an optional feature on all plans | No setup fee; no go-live time published | Live human receptionists, 24/7 | ruby.com/plans-and-pricing, checked 2026-10-10 |
| Abby Connect | Starter $165/mo, 50 Abby Minutes (AI minutes count half) | Billed at your plan's Abby Minute rate | Not itemized on the pricing page | White-glove onboarding, free trial; no go-live time published | Human receptionists, AI, or both | abby.com/pricing, checked 2026-10-10 |
| AnswerConnect | Not published | Not published | Not published | Pricing only through a contact form | Live human answering; its homepage says "real people, not automated voices" | answerconnect.com/view-pricing, checked 2026-10-10 (contact form, no prices) |
Verdict, 10 Oct 2026
- Best overall on these rules: KaiCalls (9/10). Kai Backup is $10/month for about 20 calls and Kai Line $79/month for about 170, with calendar booking on every plan, no overage charge and a price that doesn't change with call length. It is AI only: it transfers callers to your team but supplies no human receptionists.
- Next: Upfirst, Goodcall and My AI Front Desk (6/10 each). Upfirst Starter is $24.95/month for 30 calls with booking and warm transfers on every plan, and a 14-day free trial with no card; each call over 30 costs $1.50. Goodcall Starter is $79/month for 100 unique customers, and repeat callers count once. My AI Front Desk bundles chat, SMS and a CRM and publishes the fastest setup. By our arithmetic, Upfirst costs less in dollars than KaiCalls between about 20 and 110 calls a month; see KaiCalls vs. Upfirst.
- Best if you want people answering: Smith.ai, Ruby or Abby Connect. They cost more, but a trained person picks up. Abby has the lowest published human price at $165/month. Smith.ai bills per call rather than per minute, and its $2,100 Pro plan includes 10 free transfer destinations for larger teams. See KaiCalls vs. Smith.ai.
- Watch the entry tiers of Rosie and Dialzara. Both are cheap to start, but neither books on your calendar at that price. Compare their $149 and $99 plans instead. See KaiCalls vs. Rosie and KaiCalls vs. Dialzara.
Where competitors beat KaiCalls
- Human receptionists. KaiCalls is AI-only. It can transfer a caller to your team, but Smith.ai, Ruby and Abby Connect put a trained person on the line.
- Enterprise and multi-location. Smith.ai, Goodcall, Upfirst and Abby Connect publish enterprise or custom plans with features like SLAs, volume pricing or HIPAA options. KaiCalls' largest published plan is Kai Office at $349/month.
- Trying before paying. Upfirst's trial needs no card, and Goodcall lets you build a demo agent free. KaiCalls has a free browser demo, but live calls need a paid plan.
- Published setup time. My AI Front Desk and Dialzara publish how fast you can go live. KaiCalls doesn't, and these rules don't score it.
- Price at 20 to 110 calls a month. Upfirst costs less in dollars across that range, by our arithmetic from its published prices. See KaiCalls vs. Upfirst.
Prices only? See the cheapest AI answering service. Deciding between a person and software? See answering service vs. AI receptionist, or run your numbers in the ROI calculator.