Updated December 17, 2025
TL;DR: If you run an agency and your growth depends on cold email, choose the platform that scales accounts and deliverability, not headcount. Cold email delivers 18× lower cost per meeting ($152.73 vs $2,777.78), 10× higher ROI ($36-$42 per $1 vs $1-$3.50), and you can reach 10,000 prospects monthly for under $500 versus $50,000+ for cold calling. Instantly gives you unlimited sending accounts on a flat fee, built-in warmup, and AI reply handling so you scale clients without compounding software costs.
If you run an agency, every quarter your clients demand meetings, and every missed week compounds pressure. You've likely invested in cold calling, trained SDRs, and watched costs climb as you added headcount. The data shows a different path.
When you manage 10 to 150+ sending inboxes across client domains, cold email offers something cold calling cannot match: predictable scalability without linear cost increases. I'll walk you through seven key metrics, show you exactly where cold email wins, and share the systems we use at Instantly to help you book meetings safely and cost-effectively.
Is Cold Calling Still Relevant for B2B Sales in 2025?
Cold calling still works in specific contexts, but buyer behavior and cost realities have changed the economics for agency operators.
Is B2B cold calling still effective?
I've seen cold calling deliver results when your team reaches decision-makers directly, but the average cold call success rate sits between 0.3% and 4.8% for booking meetings and closing sales. Research from Cognism shows that gatekeepers block approximately 70-80% of cold calls before they reach decision-makers, and it takes an average of 8 attempts to finally reach a prospect, consuming hours per booked meeting.
The math gets worse when you factor in buyer availability. In 2025, only 19% of American adults answer calls from unknown numbers, and most calls go straight to voicemail.
Cold calling offers one advantage: immediate, real-time qualification. When a prospect picks up and engages, you can adapt your pitch dynamically. For high-value enterprise accounts or industries where personal relationships dominate, a skilled SDR on the phone remains valuable. However, buyer preference data tells a different story about where most decision-makers want to engage.
"This company has the best cold email outreach system that I have ever used. It's very effective when used correctly. The support system and staff are also very great. Any problem that I have ever faced has been resolved by them extremely efficiently." - Owen Palmer on Trustpilot review
Cold Calling vs Cold Email: Which Has Better Success Rates in 2025?
Here are the raw numbers that drive agency economics.
What Are the Average Conversion Rates for Cold Email vs Cold Calling?
Average cold call conversion rates range from 2% to 5% for conversations, but sales conversion often drops below 1%. By comparison, cold email campaigns typically achieve 1% to 5% conversion from initial contact to paying customer. More importantly for agencies, well-optimized campaigns can push reply rates to 8-12%, and personalized emails can reach up to 18% response rates.
"We use it regularly to contact physicians about our opportunities, and it simplifies the process of creating email campaigns from our physician lists. Additionally, we have been seeing excellent response rates." - Theo S. on G2 review
How Many Prospects Can You Reach with Cold Email vs Cold Calling Per Month?
The average B2B salesperson makes 52-68 calls per day, with each call requiring individual effort and immediate availability. Scaling cold calling means hiring more SDRs at $80,000-$100,000 OTE per person.
For warmed-up email accounts, you can realistically send 50 to 100 emails daily. With automation platforms, you send hundreds or thousands of personalized emails simultaneously.
What's the Real Cost Per Meeting for Cold Email vs Cold Calling?
The economic gap is stark. To reach 10,000 prospects monthly via cold calling requires roughly 7 SDRs at 1,500 calls each, translating to approximately $50,806 per month when you factor in compensation ($7,083/month/SDR), dialer software ($75/month/SDR), and CRM integration ($100/month/SDR).
To reach 10,000 prospects monthly with cold email costs approximately $489 per month, including platform fees ($75), domains and mailboxes ($150), lead sourcing ($49), email verification ($15), and personnel oversight ($200).
Comparative research on cold calling versus email outreach performance shows cold email converts at 1.5 meetings per 100 attempts versus just 0.08 for cold calling. The data reveals consistent patterns across industries.
| Metric | Cold Calling | Cold Email |
|---|---|---|
| Conversion to meeting | 0.08 per 100 attempts | 1.5 per 100 emails |
| Cost per lead | $2,777.78 | $152.73 |
| ROI per $1 spent | $1-$3.50 | $36-$42 |
| Buyer preference | 49% prefer phone | 80% prefer email |
| Metric | Cold Calling | Cold Email |
|---|---|---|
| Monthly cost for 10,000 prospects | ~$50,806 | ~$489 |
| Daily volume per rep | 52-68 calls | 50-100+ emails |
| Primary barrier | Gatekeepers block 70-80% | Deliverability (requires warmup) |
Sources: Agile Growth Labs, Martal Group, Rep.ai, Cognism
Why cold email offers superior scalability and ROI for agencies
Scaling email outreach shouldn't force you to choose between growth and profitability. The infrastructure you choose determines whether adding clients compounds costs or protects margins.
How Do Unlimited Email Accounts Reduce Cold Outreach Costs for Agencies?
Traditional cold email platforms charge per seat, per inbox, or per send, which penalizes growth. When you add a new client or expand a campaign, your software costs multiply. I've watched agencies hit revenue targets but miss profit goals because their tools taxed scale.
Instantly offers unlimited email accounts and built-in warmup on all plans, starting at $37 per month for the Growth plan. You can scale from 10 inboxes to 100+ without software costs multiplying linearly. For agencies managing multiple client domains, this directly impacts profitability. Our guide on 7 ways agencies can scale cold email outreach details how flat-fee models protect margins.
"Instantly.ai is honestly one of the best outreach tools I've used. Setup is quick, the interface is super clean, and it just works. Emails send smoothly, deliverability stays high, and the analytics make it easy to tweak campaigns." - Trustpilot review
How Do You Maintain High Email Deliverability When Sending at Scale?
Deliverability determines whether your emails land in the primary inbox or spam. A burned domain means a burned client relationship.
We provide built-in warmup and a private deliverability network of 4.2M+ accounts to help new inboxes earn trust faster. Our automated inbox placement tests and alerts continuously monitor where your emails land across Gmail, Outlook, and Yahoo, so you can adjust before deliverability slides.
On Light Speed plans, SISR (Server & IP Sharding & Rotation) distributes sending volume across dedicated and private IP pools, isolating client domains and protecting sender reputation at scale.
"I absolutely appreciate Instantly's unlimited email warm-up feature. It allows me to properly warm up multiple email accounts, crucial for the success of my email campaigns." - G2 review
This infrastructure matters because proper warmup and list hygiene materially improve inbox placement compared to un-warmed or un-verified sending.
How Do You Find and Target the Right B2B Prospects for Cold Email Campaigns?
Cold calling requires sourced lists, manual dialing, and wasted time on gatekeepers. Cold email allows you to target precisely and scale instantly.
Our SuperSearch includes 450M+ B2B leads with waterfall enrichment across 5+ providers, LLM-assisted data enhancement, and AI templates. You can build highly targeted lists based on industry, job title, company size, and technology stack, then export directly to campaigns without switching tools.
"They specialize in getting emails delivered at a much higher rate than our previous email provider, and make it generally easy to find contacts, and use AI to assist in writing emails." - G2 review
Clean data and systematic list hygiene directly impact deliverability and reply rates. Our article on what thousands of cold email campaigns taught us about data hygiene details the verification and segmentation steps that protect client domains.
How to Increase Cold Email Reply Rates and Book More B2B Meetings
Raw volume means nothing if your emails don't convert. Here's how to turn scalability into booked meetings.
What Cold Email Subject Lines Get the Highest Open Rates?
Personalized subject lines boost open rates by 50%, and personalized emails achieve six times higher transaction rates than generic blasts.
Effective personalization goes beyond inserting a first name. Keep subject lines under 50 characters, reference a specific trigger (their LinkedIn post, company news, competitor mention), and A/B test 2-3 variants per campaign. Track which patterns drive >40% opens in your vertical, then build a swipe file for junior team members to replicate.
Our video breakdown covers what works in 1,000,000 cold emails analyzed with subject line patterns that consistently outperform generic templates.
When Is the Best Time to Send Cold Emails for Maximum Response?
Targeted, multi-touch campaigns significantly increase engagement compared to single-touch outreach. Send emails during business hours in your prospect's local time zone. For B2B, Tuesday through Thursday mornings (8:30 a.m. to 10:30 a.m.) generally perform best.
How Can AI Help You Respond to Cold Email Replies in Under 5 Minutes?
Manual reply management creates bottlenecks as you scale. When replies sit unanswered for hours, conversion rates drop and prospects move on.
Our AI Reply Agent auto-handles lead replies in under 5 minutes. You can configure it in Human-in-the-Loop mode (AI drafts responses, you approve via Slack) or full Autopilot mode for common objections. The feature costs 5 credits per AI reply, with transparent pricing and no hidden fees.
"Simple and well-designed UX, effective support from both humans and AI for small questions. Additionally, the AI is capable of entering campaign configurations and applying fixes, which is a huge time saver!" - G2 review
AI Reply Agent integrates with your unified inbox (Unibox), ensuring no lead waits while your team focuses on qualified conversations. Our guide explains why most AI reply agents underperform and how to fix it with configuration best practices.
Essential cold email steps for agencies:
- Warm up new inboxes for 30 days before sending cold campaigns (5 to 15 to 30 emails per day ramp).
- Verify all email lists to keep bounce rates at or below 1%.
- Personalize subject lines and first sentences using prospect-specific details.
- Test 2-3 copy variants per campaign to identify top performers.
- Set send windows to business hours in the prospect's local time zone.
- Build 4-6 step sequences with 3-5 day intervals between follow-ups.
- Monitor deliverability weekly using Inbox Placement tests.
- Use AI Reply Agent to respond to leads within 5 minutes.
Our full cold email marketing course walks through these steps in detail with campaign templates.
When to combine cold calling and cold email for maximum impact
Cold email beats cold calling on most scalability and cost metrics, but smart multi-channel sequences can improve conversion for high-value accounts.
Should You Combine Cold Email and Cold Calling for Enterprise Accounts?
Combining email and SMS delivers 30-40% higher response rates than email alone. For enterprise accounts worth $50,000+ ARR, adding a phone touchpoint after email engagement can accelerate deal velocity.
Structure your sequence like this:
- Day 1: Personalized cold email (establishes context).
- Day 3: Email follow-up (shares case study or social proof).
- Day 6: LinkedIn connection request (builds familiarity).
- Day 9: Second email follow-up (asks a direct question).
- Day 12: Cold call attempt (references the prior emails).
The key is that the call comes after the prospect has seen your name multiple times. This reduces the intrusive perception and increases the likelihood they pick up.
How to Use Cold Email Before Cold Calling to Improve Connection Rates
When your SDR dials and says, "I sent you an email last week about [specific value prop], did you get a chance to review it?" the conversation starts from context rather than interruption. This approach mitigates the biggest cold calling pitfalls: intrusiveness and gatekeeper blocking.
Our guide to combining email and text messaging for sales details orchestration strategies and compliance protocols for multi-channel outreach.
Why Do Cold Calling and Cold Email Success Rates Vary So Much?
The metrics I've shared represent averages across thousands of campaigns, but your actual results will vary based on offer, list quality, and execution.
You'll see cold call conversion rates reported anywhere from 0.3% to 4.8%. This variance stems from industry differences, how "conversion" is defined (conversation versus meeting booked versus closed deal), and SDR skill level. Studies show that stating the reason for calling can double success rates, and personalized approaches consistently outperform generic scripts.
The takeaway: cold calling can work, but the median outcome is far below what well-executed cold email delivers at scale. Our article on calculating and lowering cost per meeting provides a detailed calculator and benchmarks.
Ready to apply this playbook and prove ROI for your clients? Try Instantly free and use our ramp templates, deliverability network, and AI Reply Agent to scale cold email campaigns safely. Our agency founder's guide to scalable outbound lead generation walks through proven strategies to protect sender reputation and improve agency profitability.
Frequently Asked Questions
Does B2B cold calling still work in 2025?
Yes, but success rates average only 2.3% for booking meetings, and most calls go to voicemail. It works best for high-value enterprise accounts after email warming.
What are the biggest challenges in B2B cold calling?
Gatekeepers block 70-80% of calls, only 19% of adults answer unknown numbers, and leaving voicemails reduces future connection rates by 28%. Scaling requires hiring more SDRs at $80,000+ OTE each.
How many cold emails should I send per day per inbox?
Start with 10-20 emails per day for new accounts during warmup, then ramp to 50-100 daily once warmed. Never exceed 30 emails per inbox per day during initial campaigns to protect sender reputation.
What cold email reply rate should I expect?
Average cold email response rates fall between 8-9%, but personalized campaigns can reach 18%+ reply rates. Aim for 5-10% replies and 1-2% meeting bookings as a realistic target.
How much does it cost to reach 10,000 prospects with cold email versus cold calling?
Cold email costs approximately $489 per month for 10,000 prospects (platform, domains, leads, verification), while cold calling costs approximately $50,806 per month (7 SDRs, dialer, CRM). Cold email cost per lead is $152.73 versus $2,777.78 for cold calling.
Can I combine cold calling and cold email?
Yes, multi-channel sequences combining email and phone deliver 30-40% higher response rates for high-value accounts. Use email to establish context, then call after 2-3 email touchpoints.
How does Instantly help improve cold email deliverability?
We provide unlimited email warmup and a private deliverability network of 4.2M+ accounts, automated inbox placement tests, and SISR on Light Speed plans. These features help emails land in primary inboxes.
What ROI can I expect from cold email versus cold calling?
Cold email generally produces substantially higher ROI than cold calling due to automation, lower marginal costs, and scale. Cold email's automation and scalability drive significantly higher returns for most agencies.
Key Terminology Glossary
B2B cold calling: Directly contacting business decision-makers by phone who have not previously expressed interest, typically for lead generation or appointment setting.
Cold call conversion rate: The percentage of cold calls that result in a booked meeting or qualified lead, typically ranging from 0.3% to 4.8% in B2B sales.
Decision-maker: The individual within an organization who has the authority to approve a purchase or partnership.
Buyer receptiveness: The willingness of a potential buyer to engage with unsolicited outreach.
Sales pipeline: A visual representation of where prospects are in the sales process.
Lead generation: The process of identifying and attracting potential customers for a business.
SDR (Sales Development Representative): A sales professional focused on outbound prospecting and qualifying leads.
AE (Account Executive): A sales professional responsible for closing deals with qualified leads.
Deliverability: The ability of an email to successfully reach the recipient's primary inbox.
Warmup: The process of gradually increasing email sending volume to build sender reputation.
Sender reputation: A score assigned to an email sender that determines if emails land in the inbox or spam.
List hygiene: The practice of cleaning and maintaining an email list to remove invalid or unengaged contacts.
Spin syntax: A technique using variations in email copy to avoid detection by spam filters.
Send windows: Specific time frames during which emails are sent to optimize open and reply rates.
Reply rate: The percentage of sent emails that receive a response from the recipient.
Booked meetings: The number of appointments scheduled with prospects as a result of outreach.
Unified inbox (Unibox): A centralized platform for managing all email replies and conversations.
SuperSearch: Instantly's integrated database of B2B leads for prospecting.
Credits: A unit used within Instantly for services like SuperSearch lead generation or AI Reply Agent actions.
Throughput: The volume of emails or actions processed by a system over a given period.
Primary inbox: The main folder where legitimate and important emails are delivered.
SISR (Server & IP Sharding & Rotation): A deliverability technique using multiple servers and IPs to distribute sending volume.
