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Get the best email warmupⓘ service comparison in your search for Instantly.ai alternatives. Compare these email deliverabilityⓘ warmup tools and find the best platform for improving your email deliverabilityⓘ and sender reputation.

Compare email deliverabilityⓘ warmup tools at a glance. Check out the table below for a quick rundown of key features and highlights, followed by more detailed descriptions of Instantly.ai and ZeroBounce below.
| Instantly.ai | ||
|---|---|---|
| Supports | ZeroBounce-managed (automated) -
| Any inbox with SMTP |
| Account listings & daily limits | Starts at: 250 Warmup Seeds 2 Accounts Replies are dynamically based on engagement rules and can go up to 35% *A warmup seed can perform up to 5 actions per email from a single warmup account. These actions may include opens, clicks, favorites, replies, and similar interactions. | Unlimited accounts and sending Features such as Read Emulation and weekday sending are not available in the Growth plan. |
| Methods | Automated sending OR Self-managed sending option Emails sent to privately owned seed email accounts | Automated sending to its Deliverability Network, which contains other warmup users |
| Email content used | User-provided email content for self-managed option AI-generated content for ZeroBounce-managed option |
To help you get the best email warmup service comparison, let’s compare Instantly.ai and ZeroBounce in-depth to learn more about each platform’s features.
Which mailboxes can I use with Instantly.ai?
ZeroBounce - Get email warmup for any inbox that supports SMTP
Instantly.ai - Get email warmup for any inbox that supports SMTP
Both Instantly.ai and ZeroBounce support email warmupⓘ services for virtually any email service provider. Before subscribing to either platform, check with your provider to ensure SMTP is supported.
Account limitations, sending limits, and warmup listings
After creating a listing with your email deliverabilityⓘ warmup tool, the email warmupⓘ process can begin. To better understand how the process works, let’s look at how each platform describes its monthly plan offerings.
250 Warmup seeds
2 accounts/mailboxes
Instantly.ai
Unlimited email warmupⓘ
Starting Growth plan supports basic warmup features
Hypergrowth plan and above required for warmup actions, aka “Read emulation”
Instantly.ai is an attractive email warmup option due to its competitive pricing and “unlimited” warmup. Instantly.ai will gradually aim to improve your domain’s by increasing the volume of emails it sends daily.
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Comparatively, ZeroBounce’s Warmup service provides all of the necessary features regardless of your subscription tier. Its plans are described by the promised number of warmup seeds. The number of emails sent will vary and increase based on your current Warmup performance. A gradual increase in sending accompanied by consistent positive email engagement yields more reliable domain reputation improvement over time.
Scheduled sending
For many users, the automated email warmupⓘ process is all that’s required. However, if you want more detailed control over your business’s warmup process, you need to examine each company’s plans.
With the ZeroBounce-managed option, the Warmup automation will strive to emulate your historical sending patterns and behaviors.
However, if you’re more comfortable with complete control over the emails sent for Warmup, you can use the self-service option. With this option, ZeroBounce provides a list of seed email addresses for you to use, and you can use and schedule your real email campaigns and templates on your schedule. ZeroBounce will provide recommendations on the ideal sending schedule and volume.
Instantly.ai
Scheduling is not available with the initial Growth plan. Emails will be sent on any given day based on the Warmup tool’s decision.
By subscribing to Hypergrowth and above, you can control if emails are sent on weekdays only or on a mixture of weekdays and weekends.
Instantly.ai reporting dashboard
Instantly.ai provides a sophisticated and clean Warmup reporting dashboard that makes it easy to track your improvements.
Here’s a quick rundown of Instantly.ai’s reporting features, followed by ZeroBounce for comparison:
Track your Overall Inbox Score (percentage of emails reaching the inbox)
Lifetime Inbox score improvement
Today and Last Run statistics
All-time Warmup summary
Email authenticationⓘ and alignment tracking
ZeroBounce ONE™ package featuring Warmup
Blacklist monitoring
DMARC monitoring
Instantly.ai
Customizable engagement rules
Instantly.ai offers more advanced control of its email warmupⓘ tool with the Hypergrowth plan. With its starting Growth plan, you can expect the core email warmupⓘ tool with basic sending features and little ability to customize.
With the higher plan, you’ll get access to additional email warmupⓘ features, including:
Instantly.ai
Read Emulation - Instantly.ai attempts to mimic actual human behavior by opening and reading through emails in realistic ways.
Weekdays-Only - You’ll be able to customize your schedule for sending emails. This is ideal for many businesses that only email on weekdays.
Daily Limits - You’ll also be able to set limits on how many emails are sent daily and adjust the rate at which you would like to receive replies.
When comparing ZeroBounce vs. Instantly.ai, ZeroBounce’s Warmup includes all available features regardless of subscription tier.
Customize volume and engagement rules at any time - Warmup automatically adjusts your sending volume and engagement based on your goals. You can adjust this manually at any time through your settings.
Weekdays-only - You can switch between a mixture of weekends and weekdays only just by switching a toggle.
Adjust time zone - Update your time zone preference at any time.
Email deliverabilityⓘ checks
Depending on your current email warmupⓘ progress, you may want to test out an actual email campaign to see where it lands.
ZeroBounce ONE™ includes the Inbox Placement Tester alongside its Warmup service. This test allows you to send an actual business email to 20+ well-known email service providers, find out where it lands, and get feedback on any discovered errors.
![[object Object]](/_next/image?url=%2Fassets_next%2Fzerobounce-vs-instantly-ai%2Fwarmup-comparison-warmy.webp&w=1920&q=75)
The is recommended for essential email campaigns to avoid possible errors keeping you from the inbox regardless of your domain reputation.
Comparatively, Instantly.ai offers no dedicated tester.
Does ZeroBounce have access to read my emails?
Any email warmupⓘ service will read the emails sent to the privately-owned seed email addresses, so that they can perform realistic, authentic behaviors.
However, ZeroBounce doesn’t read any emails found in the connected inbox. The company maintains strict adherence to security and privacy regulations to protect your data.
Whether you’re uploading your data for verification or sharing your accounts for email warm-up, protecting and securing your business data is vital.
ZeroBounce is firmly committed to providing users with military-grade security and data protection. Its detailed outlines the company’s accreditations and practices.

Instantly.ai
For comparison, Instantly.ai is fully compliant with GDPR and other relevant data protection regulations.
Who can benefit from the best email warmupⓘ tools? Any business that sends emails, especially if you have other professionals outside of your marketing team using email for outreach.
Sales and outreach professionals
When it comes to domain reputation, your marketing team isn’t likely the cause of negative impacts. It’s more likely that others in your company are uploading new, unverified contacts and engaging in other sending practices that hurt your deliverability.
To put it plainly, many of those cold outreach emails are going right to the spam folder.
Email warm-up isn’t meant to protect bad actors. You must sync up with your teammates, verify new leads, and stay within recommended daily sending limits. But email warm-up can help improve and repair your domain right now.
Warm up new business domains
Whether you’re a new business or looking to create separate subdomains for your sales teams, email warm-up is critical.
Domain reputation is like a credit score. While you may not have bad credit, having no credit also limits what you can accomplish.
Email warmupⓘ tools help gradually build that reputation over time with increased sending and positive engagement. This effort helps build the trust of internet service providers and shows that your business is committed to safe email-sending practices.
Email marketers
While we said that marketers likely know the best practices, it’s not always true. As an email validationⓘ tool for 500,000+ customers, we know firsthand that not everyone is cleaning their lists enough.
If you need an Instantly.ai alternative, look no further.
Try email warmupⓘ with ZeroBounce ONE™, your all-in-one solution for unbeatable email deliverabilityⓘ.
Reach out to our sales team now, and we’ll help set up the right package for you.

Instantly.ai is an outreach, lead generation, and CRM platform that helps businesses assess leads, build email engagement, and maximize email deliverability.
The vital detail you should note that is that sending volume is only one factor that impacts domain reputation and deliverability. Sending too many emails too fast will indeed prompt internet service providers to flag your domain and relegate emails to spam. You need to introduce ISPs to your domain gradually over time; hence, there is a need for a gradual warmup.
However, sending alone is not enough to provide consistent email deliverabilityⓘ improvements. It’s not enough to send an email; other factors impact your reputation, including open rates, clickthrough rates, favorites, unsubscribe rates, spam complaints, etc. How the user responds to the email is just as, if not more, important.
Instantly.ai will open and reply to emails within its Deliverability Network. However, advanced features such as Read Emulation,which attempts to emulate a real person reading and interacting with your email, are only available with higher-tier plans.
Overview - Includes the number of emails sent, emails that landed in the Inbox, emails saved from spam, and received warmup emails.
Daily and last 7-day sending statistics
Email deliverabilityⓘ score tracker with alerts for cold email readiness
Spam detection - Alerts users when deliverability issues arise so that they can resolve them fast
Choose start-up dates - Start, pause, and adjust Warmup on your preferred date.
If you’re sending out campaigns to dirty lists, your bounce rate climbs, your engagement rate falls, and your reputation suffers.
Email warmup tools can help repair the damage caused by lazy email marketing practices. What’s better is that an email warm-up service can actively improve your email deliverability automatically, allowing you to focus on key aspects of your campaigns, including copy and creative.
| AI-generated content |
| Schedule sending | Deliver emails whenever you prefer with the self-managed Warmup option | With Hypergrowth plan and above |
| Multiple languages | No | No |
| Reporting dashboard | Yes | Yes |
| Placement & category monitoring | Yes | Yes |
| Authentication alignment tracking | Yes | Yes |
| Customizable engagement rules | Yes | With Hypergrowth plan and above |
| Deliverability checks (check if emails land in spam or promotions) | Yes, included with ZeroBounce ONE™ (Inbox Placement Test - includes testing for 20+ domains) | No |
| Military-grade security and privacy compliance | SOC 2 Type 2 certification ISO-27001 certification GDPR, CCPA, HIPAA, and PCI compliance | Compliance with GDPR and other relevant data protection laws |
| 24/7 customer support | Yes | No |
| Does it require IMAP? | No, ZeroBounce only sends emails. It doesn’t read any of them to protect your confidentiality. | Yes |
| Cancel any time | Yes | Yes |
| Supports |
ZeroBounce ZeroBounce-managed (automated) -
|
Instantly.ai Any inbox with SMTP |
| Account listings & daily limits |
ZeroBounce Starts at:250 Warmup Seeds 2 Accounts Replies are dynamically based on engagement rules and can go up to 35% *A warmup seed can perform up to 5 actions per email from a single warmup account. These actions may include opens, clicks, favorites, replies, and similar interactions. |
Instantly.ai Unlimited accounts and sendingFeatures such as Read Emulation and weekday sending are not available in the Growth plan. |
| Methods |
ZeroBounce Automated sendingOR Self-managed sending option Emails sent to privately owned seed email accounts |
Instantly.ai Automated sending to its Deliverability Network, which contains other warmup users |
| Email content used |
ZeroBounce User-provided email content for self-managed optionAI-generated content for ZeroBounce-managed option |
Instantly.ai AI-generated content |
| Schedule sending |
ZeroBounce Deliver emails whenever you prefer with the self-managed Warmup option |
Instantly.ai With Hypergrowth plan and above |
| Multiple languages |
ZeroBounce No |
Instantly.ai No |
| Reporting dashboard |
ZeroBounce Yes |
Instantly.ai Yes |
| Placement & category monitoring |
ZeroBounce Yes |
Instantly.ai Yes |
| Authentication alignment tracking |
ZeroBounce Yes |
Instantly.ai Yes |
| Customizable engagement rules |
ZeroBounce Yes |
Instantly.ai With Hypergrowth plan and above |
| Deliverability checks (check if emails land in spam or promotions) |
ZeroBounce Yes, included with ZeroBounce ONE™ (Inbox Placement Test - includes testing for 20+ domains) |
Instantly.ai No |
| Military-grade security and privacy compliance |
ZeroBounce SOC 2 Type 2 certificationISO-27001 certification GDPR, CCPA, HIPAA, and PCI compliance |
Instantly.ai Compliance with GDPR and other relevant data protection laws |
| 24/7 customer support |
ZeroBounce Yes |
Instantly.ai No |
| Does it require IMAP? |
ZeroBounce No, ZeroBounce only sends emails. It doesn’t read any of them to protect your confidentiality. |
Instantly.ai Yes |
| Cancel any time |
ZeroBounce Yes |
Instantly.ai Yes |
Latest comparison as of October 2024
Disclaimer: The third party's name is utilized for comparison purposes only and is the trademark of its respective owner. ZeroBounce claims no rights whatsoever in the use of such name and/or any related trademarks. ZeroBounce is not affiliated with the third party referenced on this page.
ZeroBounce ONE
™
Everything you need for inbox success—tools, credits, insights, and savings, all in ONE plan.
Credits and Tools
$99 /mo
Price per credit: 0.009
Enter your quantity. *Minimum 25,000
Customize your monthly plan.
Includes everything from Pay-as-you-go plus the following tools:
Activity Dataincluded
15% Discounton Pay-As-You-Go Credits and Autopay
Blacklist Monitors are scanned every 8 hrs
