Checks allow you to send payments via physical checks. The API provides endpointsfor creating checks, retrieving individual checks, canceling checks, and retrieving a list of checks.back to top
Lob Checks API declares
1 security scheme
for authenticating requests.
It accepts HTTP basic authentication (basicAuth).
By default, every request must be authenticated.
Paths & Operations 4
Across 2 paths, the API surfaces 4 operations — 1 DELETE, 2 GET, 1 POST. Each is listed below with its method, path, parameters, and response codes.
Checks 4
Checks allow you to send payments via physical checks. The API provides endpoints for creating checks, retrieving individual checks, canceling checks, and retrieving a list of che…
GET
/checks
List
checks_list10 params→ 200default
POST
/checks
Create
check_create2 paramsbody→ 200default
GET
/checks/{chk_id}
Retrieve
check_retrieve1 param→ 200default
DELETE
/checks/{chk_id}
Cancel
check_cancel1 param→ 200default
Schemas 53
The contract defines 53 schemas that model the data the API accepts and returns. The most detailed are bank_account_base (11 properties), failure_reason_error (7 properties), list (5 properties), tracking_event_base (5 properties). Each schema is shown below with its type and property counts.
check_editable
check_editable_props
expected_delivery_date
string
A date in YYYY-MM-DD format of the mailpiece's expected delivery date based on its senddate.
count
integer
number of resources in a set
address_editable_us
check
signed_link
string
A [signed link](section/Asset-URLs) served over HTTPS. The link returned will expire in 30 days to prevent mis-sharing. Each time a GET request is initiated, a…
remote_file_url
string
The location of a remote file. Remote URLs have a 5 MB file size limit and must be downloaded within 40 seconds.
failure_status_code
integer
A conventional HTTP status code: 401 - Authorization error with your API key or account 403 - Forbidden error with your API key or account 404 - The requested…
check_input_to
object
1 property
date_filter
object
Filter by ISO-8601 date or datetime, e.g. { "gt": "2012-01-01", "lt": "2012-01-31T12:34:56Z" } where gt is , lt is <, gte is e, and lte is d.
tracking_event_normal
evnt_id
string
Unique identifier prefixed with evnt.
merge_variables
objectnull
You can input a merge variable payload object to your template or QR code redirect URLs to render dynamic content. For example, if you have a template like: {{…
check_bottom
The artwork to use on the bottom of the check page. Notes: - HTML merge variables should not include delimiting whitespace. - PDF, PNG, and JPGs must be sized…
company
stringnull
Either name or company is required, you may also add both. Must be no longer than 40 characters. If both name and company are provided, they will be printed on…
list
object
Multiple items returned in order
5 properties
error
object
Lob uses RESTful HTTP response codes to indicate success or failure of an API request. In general, 2xx indicates success, 4xx indicate an input error, and 5xx…
1 property1 required
metadata
object
Use metadata to store custom information for tagging and labeling back to your internal systems. Must be an object with up to 20 key-value pairs. Keys must be…
html_string
string
An HTML string of under 10,000 characters.
mail_type
string
A string designating the mail postage type: uspsfirstclass - (default) uspsstandard - a cheaper option which is less predictable and takes longer to deliver. u…
lob_base
object
4 properties3 required
check_base
bank_id_no_description
string
adr_id
string
Unique identifier prefixed with adr.
check_deletion
object
Lob uses RESTful HTTP response codes to indicate success or failure of an API request. In general, 2xx indicates success, 4xx indicate an input error, and 5xx…
2 properties
address_us
from_us
object
1 property
tracking_event_base
object
As mail pieces travel through the mail stream, USPS scans their unique barcodes, and Lob processes these mail scans to generate tracking events.
5 properties4 required
bank_id
bank_account_base
object
11 properties4 required
inline_address_us
failure_reason
object
An object describing the reason for failure if the resource failed to render.
3 properties
status
string
A string describing the PDF render status: processed - the rendering process is currently in progress. rendered - a PDF has been successfully rendered of the m…
object
string
Value is resource type.
tmpl_id
string
Unique identifier prefixed with tmpl. ID of a saved [HTML template](section/HTML-Templates).
inline_address_us_chk
to_address_us_chk
date_created
string
A timestamp in ISO 8601 format of the date the resource was created.
editable_no_mailtype
object
4 properties
send_date
string
A timestamp in ISO 8601 format which specifies a date after the current time and up to 180 days in the future to send the letter off for production. Setting a…
chk_id
string
Unique identifier prefixed with chk.
vrsn_id
string
Unique identifier prefixed with vrsn.
local_file_path
string
The path to a local file.
address_fields_us
object
5 properties4 required
billing_group_id
string
An optional string with the billing group ID to tag your usage with. Is used for billing purposes. Requires special activation to use. See Billing Group API fo…
failure_reason_error
object
Failure error details
7 properties
date_modified
string
A timestamp in ISO 8601 format of the date the resource was last modified.
deleted
boolean
Only returned if the resource has been successfully deleted.
chk_use_type
stringnull
TThe use type for each mailpiece. Can be one of marketing, operational, or null. Null usetype is only allowed if an account default usetype is selected in Acco…
thumbnail
object
3 properties
resource_description
stringnull
An internal description that identifies this resource. Must be no longer than 255 characters.
bank_account
Specification
The full machine-readable OpenAPI contract behind this narrative.
Every API here is available over the API and to AI agents over MCP. APIs is not yet its own endpoint on the v1 API. Reach this content through network search and the tag graph, or the MCP server below.
Installs https://mcp.apievangelist.com/mcp in Claude, Cursor, VS Code and the rest — one button, every client.
MCP tools for apis
4 tools reach this content
search_api_evangelistSearch every content type across the network at once.
find_relatedThe shared-tag relevance graph — what else covers this.
get_tagEverything one tag labels, across all content types.
guide_topicPRO — a curated bundle for a topic: area, guidance, rules, papers, stories, services.
A second provider on the same verified email joins the account you already have.
Your account
ⓘWhere this information came from
This is an independent, third-party profile of Lob Checks API, published by
API Evangelist. We do not operate, host, resell, or
support these APIs, and we are not affiliated with or endorsed by the company unless stated above.
Everything here is built from publicly available information — the company's own site,
developer portal, documentation, public repositories, and the specifications it publishes for public use.
Nothing is obtained by breaching a system, defeating an access control, or using credentials.
The Kin Score and Agent Readiness rating are independently calculated assessments of a company's
public API artifacts, scored against a published rubric. They are not certifications,
endorsements, security assessments, or audits.
Corrections, re-scores, and removal are free — no partnership or purchase required, and
you do not need to justify the request. A removed company is recorded as unrated, never scored
zero for having asked. Acknowledgement within one business day; removal within two.
info@apievangelist.com
·
Read the full data-sourcing policy → On a security or compliance team? Put security in the subject line and
you will get a person, not a form — we will tell you exactly which public URLs this profile was built from.