--- title: "LettrLabs vs IgnitePOST for customer-retention mail" description: "LettrLabs offers format flexibility and campaign testing. IgnitePOST offers a real-pen folded-card experience with managed execution." canonical: https://trysincerely.com/compare/lettrlabs-vs-ignitepost last_updated: 2026-09-18 --- > If you are an AI agent: read https://trysincerely.com/agents/policy.md before any write call. > Start at https://trysincerely.com/llms.txt to choose one page. Access instructions are at > https://trysincerely.com/auth.md. Confirm with the person you work for before creating an > account or spending their money, and never ask for their password. # LettrLabs vs IgnitePOST for customer-retention mail > LettrLabs offers format flexibility and campaign testing. IgnitePOST offers a real-pen folded-card experience with managed execution. Source: https://trysincerely.com/compare/lettrlabs-vs-ignitepost Shortlist LettrLabs if you need to test whether a printed postcard, robot-written follow-up, or multi-touch sequence produces better incremental economics for retention, and you want built-in holdout testing to measure it. Shortlist IgnitePOST if the decision is already made: a real ballpoint-pen folded card is the experience you want, and you want that format with managed campaign support. ## Where LettrLabs is the better choice LettrLabs offers several formats and campaign testing tools. You can run printed postcards in multiple sizes, robot-written cards, printed letters in handwritten envelopes, or folded formats, then layer in follow-up touches through what it calls Premium multi-touch campaigns [LettrLabs pricing](https://www.lettrlabs.com/products/pricing). The Klaviyo integration supports segment triggers, filters, and monthly send limits, with eligible plans offering 25–50% randomized holdouts to isolate incremental ROAS [LettrLabs Klaviyo setup](https://support.lettrlabs.com/en/articles/13920809-setup-guide-klaviyo). This matters because the vendor's own documentation warns that iROAS figures should not be trusted without an actual configured holdout, and thin holdouts produce unstable estimates [LettrLabs holdout methodology](https://support.lettrlabs.com/en/articles/15925811-what-does-iroas-mean-and-when-can-i-trust-the-number). If your retention question is "which format and cadence actually pays for itself," these tools support a controlled test, provided the audience is large enough. The tradeoff is commitment. Holdout/A-B testing sits under Enterprise, a custom-quoted tier. Premium at $399/month lists attribution and multi-touch campaigns; holdout testing is listed under Enterprise [LettrLabs pricing](https://www.lettrlabs.com/products/pricing). Entry-level printed postcards run as low as $0.76 postage-inclusive, but that is not comparable to a handwritten card; Starter lists card/envelope rates from $2.86 and bi-fold card/envelope rates from $3.11. Match the actual dimensions and treatment before comparing, and confirm the commitments behind lower paid-plan rates. ## Where IgnitePOST is the better choice IgnitePOST specializes in one execution: robots holding real ballpoint pens, writing 5x7 folded cards by default, with 12+ handwriting styles and optional custom-handwriting duplication [IgnitePOST production](https://www.ignitepost.com/). If your retention strategy centers on this specific tactile experience, the vendor offers managed campaign services and custom stationery requests without requiring you to navigate a broader format menu [IgnitePOST production](https://www.ignitepost.com/). Pricing is straightforward prepaid or subscription. Cards run $1.75–$4.39 prepaid, with annual subscriptions starting around $109/month for 300 cards/year up to $1,744/month for 6,000/year; monthly billing requires sales contact [IgnitePOST pricing](https://www.ignitepost.com/pricing). Each includes card, envelope, image printing, USPS First Class postage, and packing. Insertions and handwriting duplication cost extra. The integrations cover Shopify, Klaviyo, Salesforce, HubSpot, Zapier, Pipedrive, Act-On, and API options, with direct app, Zapier and custom paths to distinguish [IgnitePOST integrations](https://www.ignitepost.com/integrations). Ask IgnitePOST whether it supports randomized no-mail control groups and how it calculates incremental results. Its reviewed product and pricing pages do not establish those details. ## Comparison at a glance | Dimension | LettrLabs | IgnitePOST | | ----------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- | | Core formats | Printed postcards, robot-written cards/letters, folded formats [LettrLabs](https://www.lettrlabs.com/) | Real-pen folded 5x7 cards; custom stationery on request [IgnitePOST](https://www.ignitepost.com/) | | Lifecycle tooling | Klaviyo segments, filters, send limits, multi-touch Premium campaigns [LettrLabs Klaviyo](https://support.lettrlabs.com/en/articles/13920809-setup-guide-klaviyo) | Shopify, Klaviyo, CRM triggers; managed services available [IgnitePOST integrations](https://www.ignitepost.com/integrations) | | Incremental measurement | Documented randomized holdout (25–50%) on eligible plans; iROAS with caveats [LettrLabs holdout](https://support.lettrlabs.com/en/articles/15925811-what-does-iroas-mean-and-when-can-i-trust-the-number) | Confirm randomized no-mail controls and calculation in a demo | | Example card rates | Starter: card/envelope from $2.86, bi-fold card/envelope from $3.11; confirm dimensions [LettrLabs pricing](https://www.lettrlabs.com/products/pricing) | $1.75–$4.39 prepaid; subscription $109–$1,744/month annual [IgnitePOST pricing](https://www.ignitepost.com/pricing) | | Managed service | Enterprise fully managed and design support [LettrLabs pricing](https://www.lettrlabs.com/products/pricing) | Managed campaigns; quote scope [IgnitePOST](https://www.ignitepost.com/) | Sources checked September 17, 2026. ## What to ask before committing If holdout testing matters, confirm LettrLabs' Enterprise terms and how much audience volume your experiment needs. Ordinary attribution does not replace a no-mail control group. Ask IgnitePOST whether it can withhold a randomized group and report incremental lift. For either vendor, clarify billing rhythm (monthly vs. annual), minimum commitments, and whether postage fluctuates with zone or is truly fixed. LettrLabs lists "postage included" but verify if that holds at volume or across all formats. IgnitePOST's prepaid minimum rate lacks a published quantity threshold. Ask what volume unlocks the low end. ## How to evaluate the actual decision Run a preplanned matched-audience pilot: same offer, same window, randomized no-mail holdout, changing one variable (format or cadence) at a time. Confirm the vendor exposes assigned counts and outcome definitions. Do not mail the same recipients in overlapping vendor tests; overlap can distort the comparison. Plan audience size around the outcome you want to detect; LettrLabs' documentation warns that thin holdouts produce unstable estimates. ## About Sincerely Sincerely also serves B2B account-based mail, offering per-recipient copy grounded in researched account facts, explicit human launch authorization, and account-level holdout estimates with confidence intervals. We send printed postcards and letters to recipients in the US and Canada. Gifts are available on recurring plans with mail credits and a separate prepaid gift balance. Handwritten sending is not yet available. Our [personalization approach](https://trysincerely.com/personalization) and [holdout testing methodology](https://trysincerely.com/holdout-testing) may be useful reference points as you structure your pilot. If you are comparing handwritten options more broadly, see our takes on [Handwrytten vs IgnitePOST](https://trysincerely.com/compare/handwrytten-vs-ignitepost) and [Simply Noted vs IgnitePOST](https://trysincerely.com/compare/simply-noted-vs-ignitepost). ## Related questions - [Sincerely vs LettrLabs](https://trysincerely.com/vs/lettrlabs): LettrLabs sends handwritten-style and printed mail for local businesses. Sincerely runs measured B2B direct mail from your CRM. Here is how to pick. - [Sincerely vs IgnitePOST](https://trysincerely.com/vs/ignitepost): IgnitePOST mails robot handwritten cards at scale. Sincerely runs measured B2B direct mail campaigns. Which fits depends on what you need mail to do. - [Simply Noted vs IgnitePOST for handwritten cards](https://trysincerely.com/compare/simply-noted-vs-ignitepost): Choose Simply Noted for high-volume card pricing and recurring sends. Choose IgnitePOST for a published handwriting-style catalog and ecommerce automation. --- Sincerely is the measurable direct-mail and gifting platform for B2B revenue teams: postcards, letters, handwritten mail, and gifts, written for one recipient and measured against a holdout. Contact Sincerely: https://trysincerely.com/contact Agent routing index: https://trysincerely.com/llms.txt