Application fields
LENDING / DATA REFERENCE

Application fields

AC accepts a defined list of application fields and rejects fields not on that list. Additional lending validation applies, including required and conditionally required values.

Important distinction: A field being accepted by AC does not guarantee that an application containing it is valid for the downstream lender marketplace. Follow the required and conditional field guidance below, along with any additional integration requirements provided by AC.

Core required and conditional fields

Field Requirement Notes
loan_amount Required Whole GBP, integer
loan_purpose Required Numeric purpose code
loan_term Required Months
first_name, last_name Required Customer legal name
dob Required YYYY-MM-DD; age eligibility applies
marital_status Required Supported numeric code
title or gender Conditional Send gender if title is not provided
email Required Customer email
mobile_phone or home_phone Conditional At least one phone number
residence_type Required Supported numeric code
postcode, city, county Required Current UK address
building_name, building_number or address1 Conditional At least one
street_name or address2 Conditional At least one
months_at_address Required At least one month
income_source Required Supported numeric code
gross_annual_income or monthly_income Conditional At least one income value
rental_mortgage_payments Required Monthly GBP, integer
terms_consent Required 1 only when customer has actually accepted the relevant terms
site_url, site_ip, client_ip Required Originating website and customer context

Additional address history, employment, expenditure, banking and consent fields may be needed to access the relevant lender panel or satisfy particular lender rules.

Field format cautions

  • Use integer GBP values where the source specification requires whole pounds.
  • Do not invent a value for a field you have not collected or for which you lack a lawful basis.
  • Phone, income, address and employment rules may vary by lender and should be verified during integration testing.
  • Include affiliate_app_id when available for traceability; use a unique, client-controlled application reference.
  • campaign_code and mode must not be submitted. AC controls them.

All accepted AC field names

These names are taken from the shared relay implementation. Inclusion on this list is not a statement that the field is optional, required or supported by every downstream lender.

Loan and identity 11 fields
affiliate_app_idloan_amountloan_purposeloan_termtitlefirst_namelast_namegenderdobmarital_statusdependent_number
Contact, current and previous addresses 25 fields
emailmobile_phonehome_phoneresidence_typepostcodebuilding_namebuilding_numberstreet_namesub_buildingaddress1address2citycountymonths_at_addressprev_residence_typeprev_postcodeprev_building_nameprev_building_numberprev_street_nameprev_sub_buildingprev_address1prev_address2prev_cityprev_countyprev_months_at_address
Employment and income 18 fields
income_sourceemployer_namejob_titlework_phonemonths_at_employergross_annual_incomemonthly_incomeemployment_industryabi_industryincome_pay_frequencyincome_payment_typenext_pay_datehas_other_household_incomebenefitsrental_incomepension_incomeadditional_job_incomeother_income
Property, expenditure and bank 15 fields
home_valueremaining_mortgagemortgage_agefinancial_dependent_costexpected_monthly_expenditure_increaserental_mortgage_paymentsexisting_loan_paymentsother_expensesbillstransportfoodbank_account_numberbank_sort_codename_of_banktime_at_bank
Consent and attribution 28 fields
terms_consentsite_urlsite_ipclient_ipclient_agentrefkeywordgclidkeyword_gclidmatch_typenetworkdevicev1v2v3v4v5i1i2i3i4i5opt_smsopt_emailopt_phoneopt_postopt_cookiewhatsapp_consent

Validation behaviour

Scenario Expected AC behaviour
Unknown field HTTP 400 invalid_request
Duplicate XML element HTTP 400 invalid_request
campaign_code or mode HTTP 400 invalid_request
XML attributes, nested elements, DTD or entity HTTP 400 invalid_request
Business-invalid value May be returned as a downstream XML result, even over HTTP 200