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Use this guidance for support if you're a software developer working with the Self Assessment Online service.
Trust and estate returns technical specifications for Self Assessment Online software developers.
Autumn Statement 23 November 2016, Scottish Draft Budget 15 December 2016 and Income Tax changes from 6 April 2017.
Partnership returns technical specifications for Self Assessment Online software developers.
Check the availability and any issues affecting the Duty Stamps online service.
Returns technical specifications for Self Assessment Online software developers.
Check the availability and any issues affecting the Electronic Data Capture Service (EDCS) online service.
Individual returns technical specifications for Self Assessment Online software developers.
Agent authorisation Construction Industry Scheme technical specifications for software developers.
Agent authorisation Self Assessment technical specifications for software developers.
The recognition process allows software developers to have their commercially available xml based products listed on GOV.UK.
Specifications for software developers on internet submissions for PAYE expenses and benefits.
Use this tool if you are a software developer wanting to produce user-defined XML test scenarios.
Add scheme adminstrator' specifications for Pension Schemes Online software developers.
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