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.com 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 54
The contract defines 54 schemas that model the data the API accepts and returns. The most detailed are bank_account_base (11 properties), failure_reason_error (7 properties), tracking_event_base (5 properties), address_fields_us (5 properties). Each schema is shown below with its type and property counts.
expected_delivery_date
string
A date in YYYY-MM-DD format of the mailpiece's expected delivery date based on its senddate.
tmpl_id
string
Unique identifier prefixed with tmpl. ID of a saved [HTML template](section/HTML-Templates).
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
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…
tracking_event_normal
count
integer
number of resources in a set
bank_account
failure_reason
object
An object describing the reason for failure if the resource failed to render.
3 properties
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…
local_file_path
string
The path to a local file.
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…
check
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 ≥, and lte is ≤.
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…
lob_base
object
4 properties3 required
html_string
string
An HTML string of under 10,000 characters.
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…
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…
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…
inline_address_us_chk
check_base
bank_account_base
object
11 properties4 required
from_us
object
1 property
adr_id
string
Unique identifier prefixed with adr.
check_editable_props
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…
date_created
string
A timestamp in ISO 8601 format of the date the resource was created.
bank_id_no_description
string
check_editable
list
object
Multiple items returned in order
5 properties
resource_description
stringnull
An internal description that identifies this resource. Must be no longer than 255 characters.
to_address_us_chk
date_modified
string
A timestamp in ISO 8601 format of the date the resource was last modified.
bank_id
evnt_id
string
Unique identifier prefixed with evnt.
print_speed
stringnull
A string designating the mail speed type: core - 2 production business days
inline_address_us
address_editable_us
address_fields_us
object
5 properties4 required
failure_reason_error
object
Failure error details
7 properties
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…
address_us
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…
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
vrsn_id
string
Unique identifier prefixed with vrsn.
deleted
boolean
Only returned if the resource has been successfully deleted.
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.
chk_id
string
Unique identifier prefixed with chk.
object
string
Value is resource type.
editable_no_mailtype
object
4 properties
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
thumbnail
object
3 properties
check_input_to
object
1 property
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: {{…
Specification
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