Accurate individual and partnership self-assessment returns with full tax computations, prepared and filed under your brand.
Every accounting practice knows the pressure of self-assessment season. From October onwards, the workload ramps up as hundreds of individual and partnership returns need to be prepared, reviewed, and filed before the 31 January deadline. Outsourcing self-assessment to Founders101 gives you the capacity to handle your full client base without burning out your team — or turning away new clients.
Our tax return specialists prepare SA100 individual returns and SA800 partnership returns covering all supplementary pages including self-employment (SA103), partnership income (SA104), property income (SA105), capital gains (SA108), and foreign income (SA106). We work with all income types ensuring every source is correctly reported and all available reliefs and allowances are claimed.
Each return includes a full tax computation showing the income tax, National Insurance, and capital gains tax liability, along with payments on account calculations where applicable. We file returns electronically via HMRC's online service using your agent credentials, and provide confirmation receipts for your records.
We send a tailored information request to each client (under your brand), collecting P60s, P11Ds, bank interest certificates, rental income details, capital gains information, and any other relevant documentation for the tax year.
Using your tax software (TaxCalc, Iris, Thomson Reuters, Sage, or others), we prepare the full return with all supplementary pages, compute the tax liability, and calculate payments on account. All reliefs and allowances are claimed where eligible.
We deliver the draft return with working papers, a tax liability summary, and a list of any items that need your attention or client confirmation. Once you and the client approve, the return is ready for filing.
We submit the return electronically to HMRC via your agent credentials, confirm the submission receipt, and provide the client with details of their tax liability and payment dates (31 January and 31 July).
Survive January season — extra capacity during peak without burning out your team
Grow your SA client base — accept more clients without hiring seasonal staff
Maximise client reliefs — our specialists claim every eligible relief and allowance
File early, avoid penalties — early preparation means clients know their liability sooner
Book a free call and we'll show you how outsourced self-assessment can ease your January workload.
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