TapTax
UK tax estimates, self-employed accounts, VAT, invoicing and Making Tax Digital for sole traders.
Connects to TapTax to help UK self-employed people estimate income tax and National Insurance, track business expenses and mileage, manage invoices, check tax codes, and prepare Making Tax Digital quarterly updates for HMRC.
Try asking Muse: "Estimate how much tax I'll owe this year based on my self-employment income and expenses."
See the most upvoted connectors
Source: Found in the official MCP Registry (uk.co.taptax/taptax) · First listed October 28, 2026
Last 24 hours
Each bar is one check, every 15 minutes. Green means it answered. Last checked 2 h ago.
Is it safe to connect?
What Muse can see: It does not ask you to sign in, so it cannot see your accounts. It only sees what Muse sends it from your request.
Before it acts: Read what Muse plans to do before you approve it, and remove the app from Muse when you stop using it.
musedirectory.ai is not part of Meta. More about how Muse handles your information
How to add it to Muse
Not in Muse's Connectors list yet, but Muse can still use it. Copy the request below and paste it into Muse. Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.
https://api.taptax.co.uk/mcpNot in Muse's Connectors list yet. Muse can still use it: its page gives you a request to paste into Muse.
Also use it in ChatGPT or Claude
TapTax is a remote MCP server, so any assistant that can add a custom connector by link can use it. Same link, same tools.
Add it to ChatGPT
- 1
Open ChatGPT settings
In ChatGPT, open Settings, then Connectors (called Apps & Connectors on some accounts).
- 2
Turn on developer mode
Under Advanced settings, switch on Developer mode. That is what lets you add a connector by link.
- 3
Create the connector
Choose Create, give it a name, paste the link as the MCP server URL, and save. If it needs a sign-in, ChatGPT asks for it here.
- 4
Use it in a chat
Start a chat, open the tools menu, pick the connector, and ask. ChatGPT asks before it runs a tool the first time.
Custom connectors need a paid ChatGPT plan, and on Team, Enterprise and Edu accounts only an admin can add them. Our "Working" label means the server answered us; it cannot tell whether your plan lets you add it. All connectors that work in ChatGPT
Add it to Claude
- 1
Open Claude settings
In Claude, open Settings, then Connectors.
- 2
Add a custom connector
Choose Add custom connector, give it a name, and paste the link.
- 3
Connect and use it
If it needs a sign-in, Claude sends you to it. Then turn the connector on in a chat from the tools menu and ask.
Custom connectors are available on paid Claude plans; on Team and Enterprise accounts an admin may need to add them. Our "Working" label means the server answered us; it cannot tell whether your plan lets you add it. All connectors that work in Claude
https://api.taptax.co.uk/mcpWhat people ask Muse to do
Technical details: safety screening, tools, response time and recent checks
Response time at the last check: 643ms. Worked in 100% of checks over 30 days.
Screening · October 28, 2026
Screened, no issues found
Screening looks for known threats and hidden instructions at the time of the check, and runs again weekly and whenever the tool list changes. It cannot see the server's code, so only connect what you need and review what Muse asks to do. How screening works.
Tools · 40
estimate_self_employed_taxEstimate UK income tax and Class 4 National Insurance for a sole trader from turnover and allowable expenses, with the take-home figure, effective and marginal rates, payments on account and tailored tips, from HMRC's published rates for the tax year. Works from the figures givencheck_tax_codeCheck whether a UK PAYE tax code (e.g. 1257L, BR, K475, 1257L W1/M1) looks right for a salary and circumstances, explain what it means, and estimate any over- or under-payment. Flat-rate codes (BR, D0, D1) are only judged when hasMultipleJobs is known; without it the verdict is ncheck_mtd_statusSay whether and when Making Tax Digital for Income Tax applies to someone, from their qualifying income: self-employment turnover plus property income, before expenses, as on their Self Assessment return. Employment and pension income do not count.get_mtd_deadlinesList the standard Making Tax Digital quarterly update periods and deadlines for a tax year, and which one is next. Updates are cumulative from 6 April.calculate_take_home_payCalculate take-home pay from a UK salary for a tax year: income tax by band (England, Wales and Northern Ireland, or Scotland), employee National Insurance, student loan repayment and pension contributions, with yearly, monthly and weekly take-home and the employer National Insurcalculate_gross_salary_for_take_homeWork out the gross UK salary needed to take home a given amount a year after income tax, employee National Insurance, student loan and a pension percentage, for a tax year (net to gross).calculate_salary_sacrificeCompare pay before and after a salary sacrifice for a pension or an electric company car: income tax, National Insurance and student loan saved, employer National Insurance saved and passed back, benefit-in-kind tax for a car, the drop in take-home pay, and for a pension the costcalculate_pro_rata_salaryWork out a part-time salary from the full-time salary and the hours or days worked compared with full time, with the take-home pay on the pro rata salary for a tax year.convert_hourly_rate_to_salaryConvert an hourly rate to the annual salary it adds up to for the hours a week and paid weeks a year given, with take-home pay on that salary for a tax year.convert_salary_to_hourly_rateConvert an annual salary to its gross hourly rate and the take-home pay per hour, for the hours a week and paid weeks a year given, in a tax year.calculate_student_loan_repaymentCalculate yearly, monthly and weekly UK student loan repayments on an income for a repayment plan (Plan 1, 2, 4 or the postgraduate loan) in a tax year.calculate_child_benefit_chargeCalculate the High Income Child Benefit Charge on an adjusted net income and the Child Benefit received in a tax year: the charge, the benefit kept, and the income the charge starts from.calculate_tax_on_multiple_incomesCalculate the combined UK tax on income from several sources in one tax year (employment, self-employment, rental profit, dividends and savings interest), allowing for PAYE tax already deducted: income tax, National Insurance, student loan, what is left to pay and take-home.calculate_pension_tax_reliefCompare a self-employed person's tax with their current and a higher personal pension contribution in a tax year: the basic-rate relief added to the pension, the reduction in the tax bill, and the net cost of the extra contribution.calculate_dividend_taxCalculate UK tax on dividends for a tax year, given the dividends and other income: the dividend allowance, tax at the basic, higher and additional dividend rates, and the effective rate.compare_salary_and_dividendsFor a limited company director, work out take-home pay from a chosen salary plus dividends paid from the remaining profit after employer National Insurance and corporation tax, with every tax and the effective rate, for a tax year.compare_limited_company_and_sole_traderCompare take-home pay as a sole trader with running the same profit through a limited company (salary plus dividends, corporation tax and accountancy cost) for a tax year, with the annual difference and an approximate break-even profit.calculate_corporation_taxCalculate UK corporation tax on a company's taxable profit for a tax year, including marginal relief between the small profits and main rates, with profit after tax and the effective rate.calculate_contractor_day_rateTurn a contractor day rate into annual and monthly income, an hourly equivalent, and take-home pay as a sole trader, through a company outside IR35 and inside IR35, with the best route and the PAYE salary that would take home as much, for a tax year.compare_inside_and_outside_ir35Compare a contractor's take-home pay working inside IR35 (deemed employment payment, employer National Insurance) with working outside IR35 through a limited company, from the day rate and working days, for a tax year. It compares pay; it does not decide IR35 status.calculate_cis_deductionCalculate the Construction Industry Scheme deduction on a payment (labour only, materials excluded) at the registered, unregistered or gross-payment rate, the amount received, and whether the year's deductions are likely to be more or less than the tax actually due.plan_quarterly_tax_set_asidePlan how much to set aside for tax as a sole trader under Making Tax Digital, from the year's profit or each quarter's profit: the income tax, Class 4 National Insurance and student loan due, monthly and weekly amounts to put away, running totals by quarter with each update deadlcalculate_mileage_allowanceCalculate the tax-free business mileage allowance for a year at HMRC's approved mileage rates for a car or van, motorcycle or bicycle, including the passenger rate, and the tax it saves at the basic or higher rate.estimate_self_assessment_penaltiesEstimate Self Assessment late filing penalties, late payment penalties and late payment interest on the tax due, from how many days late the return was filed and the tax was paid.calculate_vatAdd VAT to a net price or take it out of a gross price at the standard (20%), reduced (5%) or any other rate, with the net, VAT and gross amounts.check_vat_registrationCheck whether a turnover is over the UK VAT registration threshold for a tax year, and compare VAT payable under the standard scheme with the Flat Rate Scheme for the business's sector rate, including the first-year discount, with the cheaper scheme and the difference.check_vat_reverse_chargeWork out whether the domestic VAT reverse charge for construction services applies to an invoice, by HMRC's decision steps. Takes the yes or no answers known so far and returns the next question to answer, or the outcome with what the invoice must say.calculate_markupCalculate the selling price, profit and the equivalent profit margin from a cost and a markup percentage.calculate_profit_marginCalculate the profit margin and markup from a cost and a selling price, or the selling price needed for a target margin.calculate_invoice_due_dateCalculate the date an invoice is due from its date and the payment terms (on receipt, a number of days, end of month, days after month end, a day of the following month, or the statutory 30-day default), with the weekday and whether the terms exceed the statutory limit.calculate_late_payment_interestCalculate the statutory interest (Bank of England base rate plus 8%) and fixed compensation a business can claim on a late-paid commercial invoice under the Late Payment of Commercial Debts Act, from the amount, the due date and the payment date.calculate_capital_gains_taxCalculate UK Capital Gains Tax on selling an asset (residential property, shares, a business qualifying for Business Asset Disposal Relief, or other assets) for a tax year: the gain after costs, losses and the annual exempt amount, tax at each rate given other income, and the paycalculate_rental_income_taxCalculate UK income tax on rental profit for a landlord in a tax year, given rent, allowable expenses, mortgage interest (relieved as a 20% tax credit) and other income.calculate_savings_interest_taxCalculate UK tax on savings interest for a tax year, given the interest, any tax already deducted and other income: the starting rate for savings, the Personal Savings Allowance and the tax due.calculate_stamp_dutyCalculate the tax on buying property: Stamp Duty Land Tax in England and Northern Ireland, Land and Buildings Transaction Tax in Scotland or Land Transaction Tax in Wales, by band, with first-time buyer relief, the additional property surcharge and the non-resident surcharge wherprepare_business_documentPrepare an invoice, quote, receipt, credit note or pro forma invoice in TapTax's free document generator, without a TapTax account. Returns the totals and a link that opens the generator with the document filled in, where the person checks it, adds a logo if they like, and downlogenerate_invoice_numbersGenerate invoice numbers: the next number after a given one (keeping its prefix and zero padding), or a run of numbers in a chosen format (prefix, separator, optional year or month, number of digits) from a starting number.get_tax_positionRead the signed-in person's own TapTax account: their tax year so far, as their dashboard shows it: business income, expenses and profit counted by the filing rule, the estimated income tax and Class 4 NI, how many transactions still need a business-or-personal decision, which qulist_transactionsRead and search the signed-in person's own income and expense records in their TapTax account, newest first. Filter by tax year or dates, type, text in the description, or needsReview=true for the ones still waiting for a business-or-personal decision (the review queue). Needs noget_mileage_summaryRead the signed-in person's own mileage log in their TapTax account for a tax year: total miles, the deductible amount at the approved rates, and the most recent trips.Recent checks
Link
https://api.taptax.co.uk/mcpQuestions about TapTax in Muse
How do I connect TapTax to Muse?
Not in Muse's Connectors list yet, but Muse can still use it. Paste this into Muse: "Use TapTax to help me. It is a free service with an MCP server at https://api.taptax.co.uk/mcp. It does not need an API key. Ask me before you share anything with it." Muse asks before it shares anything with the app's site. Meta does not review apps used this way, so only use ones you trust. We tested this in the Muse app on September 24, 2026: Muse used an app's link directly this way and returned a live answer.
Is TapTax working right now?
At the last check (October 29, 2026, 09:45 UTC) the endpoint was working, answering in 643ms. Over the last 7 days it answered 100% of health checks. It is checked every 15 minutes.
Is TapTax safe to connect to Muse?
It was screened on October 28, 2026 with the result "screened, no issues found". Screening checks the domain against threat feeds and reads the tools for hidden instructions and requests for passwords or card numbers. It cannot see the server's code, so grant only the access you need.
What can TapTax do in Muse?
It exposes 40 tools, including estimate_self_employed_tax, check_tax_code, check_mtd_status, get_mtd_deadlines. For example, you could ask Muse: "Estimate how much tax I'll owe this year based on my self-employment income and expenses."
Follow TapTax
Made this app? Claim it or get a status badge
Is this yours?
This listing was added from public sources (Found in the official MCP Registry (uk.co.taptax/taptax)). If you build TapTax, claim it to correct the details and get your badge.
Paste this on your site or README. It always shows the latest check.
<a href="https://musedirectory.ai/connector/taptax"><img src="https://musedirectory.ai/badge/taptax.svg" alt="TapTax on musedirectory.ai" width="236" height="40"></a>