What types of physical mail can I send with Lob?

Lob supports three main mail types: Letters (formal correspondence, invoices, notifications with customizable color, double-sided printing), Postcards (marketing campaigns, invitations, reminders in 4x6, 6x9, or 6x11 sizes), and Checks (vendor payments, payroll, refunds, rebates with customizable memo lines and company logos). All mail is printed and mailed within 24 hours via USPS.

How does Lob address verification work?

Lob's address verification validates and standardizes addresses using USPS data. It corrects formatting, adds missing ZIP+4 codes, fixes typos, and confirms deliverability. The service returns a deliverability status: 'deliverable' (valid and deliverable), 'undeliverable' (cannot be delivered), or 'deliverable_unnecessary' (valid but additional info not needed). This reduces returned mail by up to 5% and ensures your mailings reach the correct destination.

Can I use HTML templates for personalized mailings?

Yes! Lob supports HTML templates with merge variables using the Handlebars templating engine. Create a template with placeholders like {{name}}, {{order_number}}, {{delivery_date}}, then pass actual values when creating letters or postcards. This enables personalized, scalable direct mail campaigns. Templates are reusable and can be referenced by ID when creating mailings. You can also embed CSS styling for professional-looking mail designs.

How long does it take for mail to be delivered?

Lob prints and mails all items within 24 hours of creation. Delivery time depends on the mail type selected: USPS First Class Mail typically delivers in 2-5 business days, while USPS Standard Mail takes 3-7 business days. You receive a tracking number for each piece of mail to monitor delivery status. Lob also provides expected delivery dates in API responses for planning purposes.

Lob MCP Connector for Claude

A+

Automate physical mail, postcards, checks, and address verification through Lob's print and mail API.

21 tools Official Updated Jun 28, 2026 Official Vinkius Partner

More Details Connect to Claude

Lob MCP Server enables AI agents to send physical mail directly from your applications. Create and mail letters, postcards, and checks programmatically through Lob's print and mail API. Verify US and international addresses, autocomplete partial addresses, and manage your address book. Build reusable HTML templates for personalized mailings. Perfect for automating vendor payments, customer communications, marketing campaigns, payroll checks, and direct mail operations. All mail is printed, processed, and delivered within 24 hours via USPS integration.

direct-mailprint-apiaddress-verificationautomationpostcardstransactional-mail

21 tools expose this connector's capabilities to your AI agent.

autocomplete_us_address

Autocomplete a partial US address

cancel_letter

Only works if status is still "processing". Cancel a letter before it enters production

create_address

Requires name and address_line1. Create a new address in your Lob address book

create_bank_account

Requires description, routing_number, account_number, account_type (company/individual), and signatory. Add a bank account for sending checks

create_check

Requires recipient (to), bank account ID, and amount. Optional: memo, logo, description. Create and mail a physical check through Lob

create_letter

Requires recipient (to), sender (from), and file content. Supports HTML templates with merge variables, color options, and mail type selection. Create and mail a physical letter through Lob

create_postcard

Requires recipient (to) and front design. Optional: back design, message, merge variables. Create and mail a physical postcard through Lob

create_template

Create a reusable HTML template for mailings

list_letters

Each letter includes status, tracking number, and expected delivery date. Use optional limit to control result count. List physical letters sent through Lob. Track mailings, check delivery status, and review letter history

list_postcards

Use optional limit to control result count. List physical postcards sent through Lob

list_templates

List HTML templates for mailings

verify_us_address

Verify and standardize a US address

delete_address

Delete an address from your Lob address book

get_address

Get details of a specific address

get_check

Get details of a specific check by ID

get_letter

Get details of a specific letter by ID

get_postcard

Get details of a specific postcard by ID

get_template

Get details of a specific template

list_addresses

Use optional limit to control result count. List addresses in your Lob address book

list_bank_accounts

Use optional limit to control result count. List bank accounts in your Lob account

list_checks

Track payments, audit disbursements. List physical checks sent through Lob

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