Comparison

AI SDR vs human SDR in 2026: what each does, what it costs and where the evidence stops

Choose a human SDR when the sale needs judgment, trust built in person or a negotiation. Choose an AI SDR such as Sellinger when the work is volume, speed and follow up: in our case studies the agent answered in a median of 2.3 to 2.5 minutes and people took over for the close every time. We have no head to head test of AI against people, so this page does not claim a winner.

Published by Sellinger AI. Numbers and settings checked on 19 October 2026 against the fact register. Report an error.

median agent reply to a prospect since May 2026 in the Lamothermic and referral network studies. People typing replies took a median of 29 minutes and 2.7 hours in the same studies: 2.3 to 2.5 min
studies on this site that compare AI against human conversion in a controlled test: 0
replies became a buyer side outcome in the foundry study (42 of 293), with a person closing: 1 in 7
per LinkedIn agent per month at list price (1 to 2 agents), the Outbound bundle is $249: $198

Who does which task

Tasks and who did them in the published studies
Task	Human SDR	AI agent on Sellinger
Research a prospect and write the first message	Minutes per prospect, works in working hours	Writes each message from the profile. 91% of one founder's LinkedIn messages were agent written
Follow up on silence	Depends on discipline and tooling	Follows a set cadence. Follow ups added 43% to 79% more replies across studies
Answer at 9 pm or on a weekend	Only if on call	71% of evening and weekend messages were answered before the next business morning in the foundry study
Hold a call and negotiate	Yes	No. A person closed in every study. About 14 booked calls in one study had no host
Judge an unusual question	Yes	Stops and hands over when it cannot answer, such as a price it has no answer for
Speak in many languages	Few per person	Wrote in 21 languages in the installer programme

Figures are from the linked case studies, read only data to 9 and 10 October 2026. They describe what the agent did in those campaigns, not a universal rate.

Speed, with the caveat

In the foundry study the agent's median reply was 2.3 minutes and the president's own typed replies took a median of 29 minutes. In the referral network study, the agent answered in a median of 2.5 minutes and the team's typed replies took 2.7 hours. At Hotel Pirin (a related party) the reservations agent answered guests in a median of 41 seconds, against 159 minutes where staff answered first. That last comparison is not like for like: staff answered first only where the agent had not.

Speed did not lift meetings by itself. In Sellinger's own data, cutting reply time from 19 to 2 minutes did not raise meetings per conversation. The list was the bigger lever.

A cost worksheet you fill in with your numbers

We do not quote a market salary because we could not source one to a primary page. Use your own.

Monthly cost worksheet
Line	Human SDR	Sellinger
Direct cost	Fully loaded monthly cost of one SDR: pay, benefits, equipment, management time	Live Chat from $19, Email from $39, WhatsApp and Instagram from $29, LinkedIn $198 per agent, bundles $249 to $1,199
Tools around it	Sequencing, data and dialer licences you add	Intent signals are included with every bundle. Enrichment lookups cost from $0.01 each
Ramp up	Weeks to hire and train	Usually live within a day, with approval on while you check tone
Capacity	One person's hours	Each connected account has daily limits: 20 LinkedIn invitations a day and 150 a week by default
What stays human either way	Calls, closing, hosting meetings	Calls, closing, hosting meetings

Prices are the list prices in the fact register, checked 19 October 2026. The ROI calculator runs the comparison with your own inputs.

Choose by situation

Choose a human SDR if

your buyers expect a phone call or an in person relationship before anything else,
each deal is large enough that a few carefully hand written approaches beat volume,
you have no one to host calls and review an agent's work, since the agent books and a person has to show up,
your team already has trained reps with spare capacity.

Choose Sellinger if

you need coverage across LinkedIn, email and WhatsApp without hiring for each,
replies go cold because nobody answers at night or on weekends,
follow ups are where your pipeline leaks, and you want a set cadence with a cap,
you can keep a person on the close, and want approval mode while you learn.

Many teams run both: the agent opens and follows up, and reps take the conversations that matter. See the sales leaders use case.

Common questions

Is an AI SDR cheaper than a human SDR?

At list price a LinkedIn agent is $198 a month and the Outbound bundle $249. A person's cost depends on your pay and overhead, so fill in the worksheet. The agent does not replace the call and the close.

Does an AI SDR convert better than a human?

We have no controlled test. In our studies the agent produced replies and booked calls, and people closed. Reply rates were 29% to 45% on LinkedIn, depending on audience.

Can an AI SDR replace my SDR team?

Not entirely. In every published study a person handled the close, and some bookings had no host. A common split is agent for outreach and follow up, person for the conversation that matters.

What if the agent says something wrong?

Use approval mode so a person reads each message first, and keep rules for what the agent must not promise. It stops when it cannot answer.

Is this page neutral?

No. Sellinger sells one of the options. We list where a person is better and show our own numbers with their bases.

Sources and method

Study figures from the linked case studies. Prices from the fact register, checked 19 October 2026. This page replaces the older blog post on the same question.