The formula
person per call = wage ÷ wage share ÷ time on calls × call hoursAI per finished call = AI per call ÷ finish rateaverage per call = AI per call + (1 − finish rate) × person per call- wage: the person's hourly wage in dollars
- wage share: wages as a share of total pay cost, for example 0.70 when benefits and payroll costs are the other 30%
- time on calls: the share of paid time the person spends on calls, for example 0.80
- call hours: the call's length in hours: a 6-minute call is 0.1
- AI per call: the minutes the vendor bills for the call times its all-in rate per minute, plus any fee per call
- finish rate: the share of calls the AI finishes without a person, which the buyer has to supply
How the calculator works it out
For the AI, the calculator multiplies one vendor's all-in rate per minute, at the default choices of this site's cost per minute calculator, by the minutes that vendor would bill for a call of the length entered. When a vendor leaves a part such as the phone line to the buyer, the figure leaves that part out and says so.
The person's wage is divided twice: by wages' share of total pay cost, which adds benefits and payroll costs, and by the share of paid time spent on calls, which charges each call for the paid hours off the phone.
Every call pays for the AI, finished or not, and each call the AI does not finish also pays for a person. Dividing the AI's cost per call by the finish rate gives the cost per finished call.
The worked example below uses the same arithmetic as the calculator's tests. The Bureau of Labor Statistics puts the median hourly wage of customer service representatives (occupation 43-4051) at $21.53 in May 2025. Its Employer Costs for Employee Compensation release for June 2026 says wages and salaries accounted for 70.0 percent of employer costs for private industry workers. Dividing $21.53 by 0.70 gives $30.76 an hour. If, as an example, 80% of paid time goes on calls, an hour on calls costs $38.45 and a 6-minute call costs $3.84.
Bland AI's Start plan charges $0.14 per minute of talk time, billed by the second (Per second of active call time), with the AI model inside the rate (In the per-minute rate; no token charges). Whether the phone line is inside it as well is unclear (The pricing page says telephony is billed separately, while the home page and the docs llms.txt say the per-minute rate covers telephony). At that rate a 6-minute call costs $0.84 before any phone charge. To repeat this in the calculator, choose Bland AI and enter 360 seconds, a wage of 21.53 and 80% of time on calls.
Where the finish rate tips the result
With those figures, a 60% finish rate puts each finished call at $1.40 of AI time and the average call at $2.38, which is $1.47 less than a person taking every call. At 50% the two figures are $1.68 and $2.76. At 30% they are $2.80 and $3.53, a saving of $0.31 a call. At 20% they are $4.20 and $3.92, and the AI adds $0.07 to every call.
Both results cross the person's cost at the same finish rate: the AI's cost per call divided by the person's, here $0.84 ÷ $3.84, or about 22%. A lower wage moves that point up, and so does any AI charge the example leaves out, such as a phone line billed on top of the rate.
The calculator leaves the finish rate as an input for the buyer to supply from their own calls, starting at 60%.
What the hand-off adds to the AI's bill
What a vendor bills once a person takes over the call is not in the calculator, and the vendors' rules for it differ.
Retell's rule for pay-as-you-go calls: After a transfer, only the phone fee continues. Synthflow's, for AI usage: Billing stops when a transfer completes. Bland's: Transfer time on Bland numbers is billed in addition to connected time (Transfers: $0.05 per minute on Start), so in the example the person's 6 minutes after a hand-off on a Bland number would also appear on the Bland bill. On Ultravox SIP calls a bridged cold transfer keeps two legs running (Bridged transfers: SIP minutes accrue at double rate while both legs are active). Telnyx's Voice API price list shows Call transfer $0.10 per invocation (Voice API), and that page does not say whether an AI assistant's transfers are charged at that rate.
For Vapi and ElevenLabs, this site's records hold no transfer rule. Vapi's rule on its Usage only plan: Every minute an assistant runs is billed.
Left out of the comparison
The comparison cannot say whether callers accept an AI or how well it handles a hard call, though both decide whether the finish rate entered holds up.
The person's figure leaves out hiring, training, supervision, and the desk and software each person needs, unless the reader folds them into the wage share or the time on calls. A small team that takes a few calls a day spends far less than 80% of its paid time on calls, which raises the person's cost per call. The 70.0 percent is the figure for all private industry workers; for office and administrative support occupations, the group customer service representatives belong to, table 4 of the same release gives 68.7 percent.
On the AI's side, monthly plan fees and included minutes are missing, as are charges for running more calls at once than a plan allows and the items the cost per minute calculator lists as outside its figure for each vendor. The calculator also assumes the AI talks for the whole call even when it hands over, and that the person then takes the full call length again; real hand-offs can be shorter or longer on either side. Bland's billing documentation also sets a $0.015 minimum per outbound call attempt on Bland's telephony, which the calculator leaves out.
Often confused with
- Cost per minute. The all-in rate for one billed minute of an AI call; cost per call multiplies it by the minutes a vendor bills for the call and adds any fee per call.
- Price per resolution. A vendor's charge for each call it counts as resolved under its own definition; cost per finished call on this page is worked out by the buyer from per-minute rates and the buyer's own finish rate.
- Containment rate. Counts calls that stayed with the AI, whereas resolution asks whether the caller's need was met; the finish rate this calculator wants is closer to resolution, because a caller who hangs up unhelped and rings back costs a second call.
- Loaded hourly cost. The wage plus benefits and payroll costs for an hour; this page also divides by the share of time on calls, so the person's cost per call is higher than the loaded hourly rate alone suggests.
Vendors cited on this page
Bland AI, Retell AI, Synthflow AI, Telnyx Voice AI Agents, Ultravox, Vapi. Each profile lists everything that vendor publishes, with its sources. All of them are side by side in the comparison.
Sources
- US Bureau of Labor Statistics, Occupational Employment and Wage Statistics, May 2025: 43-4051 Customer Service Representatives, national estimates (median hourly wage $21.53) read 14 Nov 2026
- US Bureau of Labor Statistics, Employer Costs for Employee Compensation, June 2026, news release USDL-26-1494 of September 9, 2026, archived copy (private industry wages and salaries 70.0 percent of employer costs) read 14 Nov 2026
- US Bureau of Labor Statistics, Employer Costs for Employee Compensation, June 2026: table 4, private industry workers by occupational and industry group (office and administrative support, wages 68.7 percent) read 14 Nov 2026
Checked against its sources on 14 Nov 2026. Vendor figures on this page open their source when clicked. Lexicost has no commercial relationship with any vendor named on this site.