CIS/Self-Employed Calculator
Calculate your student loan liability for CIS subcontractors, sole traders, and company directors. Plan for Self Assessment payments and understand CIS deduction interactions.
Self-Employed Student Loans
No automatic PAYE deductions - you must plan for annual payments via Self Assessment.
Construction Industry Scheme worker with no other income
CIS Income
Registered with HMRC, 20% CIS deductions
CIS deductions: £8,000
Net profit: £32,000
Rental, investment, other income
Quick Summary
Outcome: a balancing payment is due
£460 due on 31 January 2028
None of it comes out of your CIS deductions: those are income tax credits and never include student loan.
About £38 a month to set aside. Student loan repayments are not included in payments on account. They are collected once a year, with the balancing payment on 31 January. Your income tax and Class 4 NIC payments on account are worked out without them.
Your Self Assessment student loan, 2026-27
Counted income
£34,500
Profits after expenses, 2026-27
Total liability
£460.35
Plan 2
Due 31 January 2028
£460
After £0 deducted through PAYE
How this is worked out
£460.35 − £0 = £460.35
The balancing payment, due 31 January 2028. CIS deductions do not reduce it.
Rates, assumptions and sources
Every figure below is the 2026-27 published figure, read from this site's single source of truth at page-render time[source]. The 6% Plan 2 and Postgraduate interest cap covers the 2026/27 year only and is not assumed to continue[source].
| Plan | Threshold | Rate | Interest | Written off | Threshold freeze |
|---|---|---|---|---|---|
| Plan 2 | £29,385[source] | 9% | 4.1% to 7.1% by income, capped at 6% for 2026-27[source] | 30 years[source] | Frozen at £29,385 until April 2030 |
Write-off is counted from the April after the course ends, not from the course-end date itself, and the Plan 2 interest bands (£29,385 lower, £52,885 upper) are frozen alongside the Plan 2 repayment threshold.
This calculator also assumes
- Income used
- Profits after allowable expenses, plus counted unearned income
- Unearned income allowance
- £2,000, all-or-nothing on the total
- CIS deductions
- Income tax credits only — never student loan
- Payments on account
- None for student loans
- Balancing payment due
- 31 January 2028
Growth, inflation and long-run interest figures are assumptions, not published rates. Change them and the projection changes.
Income Analysis
| Income Source | Gross | Net (for SL) |
|---|---|---|
| CIS Receipts | £40,000 | £32,000 |
| Other Income | £2,500 | £2,500 |
| Total for Student Loan | - | £34,500 |
CIS Analysis
CIS Breakdown
Important Notes
- • CIS deductions = tax credits for income tax
- • Student loan calculated on net profit
- • SL payment separate from CIS system
- • Both due via Self Assessment
Student Loan Calculation
Liability Calculation
Payment Details
Planning & Optimization
Monthly Planning
Pay 90% directly to SLC to avoid SA late fees
Optimization Strategies
The lower of the £60,000 pension annual allowance and 40% of your counted income[source]. A personal pension contribution does not reduce the student loan charged through Self Assessment: only salary sacrifice, which lowers gross pay before payroll runs, changes a student loan figure. See the pension salary sacrifice calculator.
Expense Optimization:
- • Ensure all allowable business expenses are claimed
- • Consider equipment purchases to reduce taxable profit
- • Track vehicle expenses and home office costs
- • Allowable expenses reduce taxable profit, and so the student loan charge with it
Important Warnings
- CIS deductions do NOT include student loan repayments - separate payment required
- No PAYE student loan deductions - full liability via Self Assessment
- Unearned income over £2,000 threshold - all unearned income included
Recommendations
- Use CIS deductions as tax credits - student loan is separate payment
Understanding Self-Employed Student Loans
CIS Subcontractors
- • CIS deductions are income tax credits only
- • Student loans calculated separately on net profit
- • Both payments due via Self Assessment
- • No automatic student loan deductions
- • Must plan for annual payment by 31 January
Company Directors
- • PAYE salary may trigger some deductions
- • Dividends count as unearned income
- • Combined income determines total liability
- • Balancing payment via Self Assessment
- • Salary vs dividend optimization possible
Key Planning Points
No automatic deductions:
Unlike employees, self-employed individuals must actively plan and save for student loan payments. There are no automatic monthly deductions from your income.
Annual payment shock:
Student loan payments of £460.35 can be a significant shock if not planned for throughout the year.
Expense planning:
Business expenses reduce your taxable profit and therefore your student loan liability. Ensure all allowable expenses are claimed.
Working through an umbrella company instead:
Some contractors choose an umbrella company over CIS or a limited company to get payroll and deductions handled automatically. If that applies to you, our umbrella company and IR35 student loan calculator models that route instead.
Planning Your Self-Employed Student Loan Payments?
Self-employed student loan planning is crucial to avoid unexpected bills. Get professional guidance on managing your obligations.
Related student loan calculators
The CIS and self-employed calculator answers one specific question. For the full picture, start with our UK student loan calculator on the homepage, work out what leaves your payslip each month with the monthly repayment calculator, or check what you can borrow with the student finance calculator. Every tool on the site is listed in the UK student loan calculator directory.
- self-employed student loan calculator: what you owe through Self Assessment rather than PAYE
- umbrella and inside-IR35 PAYE calculator: deductions when you are paid through an umbrella company
- PAYE vs Self Assessment calculator: how the two collection routes compare on the same income