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Getting Started with the Dashboard

Learn how to navigate your TinyTax dashboard. Understand status icons, start filings, return to drafts, and use the company details drawer.

What Can You File?

See every company type, filing type, and tax feature TinyTax supports. Check whether your company is eligible.

Saving Your Work and Drafts

TinyTax saves automatically - no save button needed. Learn how your data is preserved and how to return to unfinished filings.

Can Overseas or Foreign Companies File CT600?

CT600 and Accounts: What's the Difference?

Currency Support — Accounts Must Be Filed in Sterling (GBP)

Do You Need AML Registration to Use TinyTax?

Does TinyTax Handle Self Assessment Tax Returns?

Filing for a UK Company as a Non-UK Resident Director

Filing Reminders Explained

Getting Help and Support

How to Edit or Correct a Draft Filing

How to Restore an Archived Company

Is TinyTax Authorised by HMRC?

Setting Up as an Accountant: Sole Trader and Partnership Practices

Starting a Filing Before Creating Your Account

Using TinyTax as a Tax Agent for Multiple Companies

Verifying Your Email Address

What company sizes are supported?

What TinyTax Does — Filing Tool, Not Bookkeeping Software

What You Can File

How to File Your First CT600

Step-by-step guide to filing your first CT600 corporation tax return with TinyTax. Covers company type selection, P&L entry, balance sheet, and HMRC submission.

How to File a Corporation Tax Return

How to file your corp tax return (CT600) with HMRC. Step-by-step guide for UK limited companies.

What Happens After You Submit

What to expect after submitting your CT600 and accounts via TinyTax. HMRC timelines, confirmation emails, and troubleshooting.

CT600 Filing Checklist

Complete CT600 checklist for UK companies. Everything you need to gather before filing your corporation tax return. Avoid mistakes and delays.

How to Pay Corporation Tax

Step-by-step guide to paying your corporation tax to HMRC. Payment methods, deadlines, and what happens if you pay late.

Associated Companies and Marginal Relief

How associated companies affect your corporation tax thresholds and marginal relief calculation in TinyTax.

CT600 Amendments

Need to correct your CT600 after filing? Learn when you can amend, the 72-hour wait, and how to do it in TinyTax.

Does this service support VAT or PAYE?

TinyTax does not currently support VAT, PAYE, or confirmation statements. Here's what we do support and where to file these.

Filing a Late CT600

Yes, you can file a late CT600 with TinyTax. Here's what penalties apply and how to submit.

Mark a Prior CT600 as Filed Elsewhere

Mark previous CT600 periods as filed elsewhere if you used an accountant or other software. Unblock current filings without refiling old periods.

Set Up Your Government Gateway

How to set up Government Gateway for your UK company. Step-by-step guide to creating your HMRC online account and enrolling for Corporation Tax services.

Common Expense Categories

Where do your business costs go on the P&L? A guide to the four expense categories in TinyTax's micro-entity format.

Property Company Accounting

How to file a CT600 for a property company with TinyTax. Covers rental income, property expenses, and Box 170.

Capital Allowances and AIA

Claim tax relief on business equipment with Annual Investment Allowance (AIA). Learn what qualifies, limits, and how to enter capital allowances in TinyTax.

Capital Gains and Disposals

How to report chargeable gains on your CT600. Covers Box 210, supported company types, and workarounds in TinyTax.

Director's Loans and the CT600A

What is a director's loan account, and when do you need the CT600A? Covers DLA, S455 tax, and what TinyTax supports.

Extended Accounting Periods

Accounting period over 12 months? Learn why you need two CT600 returns, how to split profits correctly, and which deadlines apply.

Filing for Charities and Community Benefit Societies

Can you use TinyTax for a charity or community benefit society? See which organisation types are supported.

How to Change Your Accounting Period

How to change your company's accounting period. Understand the rules for shortening or extending your financial year with Companies House.

How Losses Brought Forward Work

Use previous year losses to reduce corporation tax. Learn how brought forward losses work, where to enter them, and how they offset profits.

CIS Deductions

How Construction Industry Scheme (CIS) deductions work on the CT600. Covers Box 515 and current limitations in TinyTax.

Exchange Rate Differences

Where to enter exchange rate gains and losses on your CT600 in TinyTax. Covers FRS 105 treatment.

Prepare for Software-Only Filing

How to prepare your company for mandatory software-only filing of CT600 returns and company accounts. Timeline and checklist included.

Switch from Companies House WebFiling

Guide to switching from Companies House WebFiling to commercial software before the April 2027 deadline.

Switch from HMRC's CT600 Service

Step-by-step guide to switching from HMRC's free CT600 filing service to commercial software before the March 2026 deadline.

Download Your CT600 History from HMRC

Step-by-step guide to downloading your CT600 filing history from HMRC before the service closes in March 2026. Don't lose access to your records.

Filing for CICs and CLGs

File CT600 for Community Interest Companies (CICs) and Companies Limited by Guarantee (CLGs). Learn what TinyTax supports for these special company types.

Are Accounts Submitted to HMRC with the CT600?

Are Dividends Included in the CT600?

AVEC and Creative Industry Tax Credits — What is Supported

Balancing Charges on Asset Disposals

Capital Allowances for Company Cars on a CT600

Close Investment-Holding Company (CIHC) and Corporation Tax

CT600 Accepted but Not Showing in HMRC Business Tax Account

CT600 Fields TinyTax Does Not Include (Exporter, Bank Details, Expenses)

CT600 Values Missing or Blank — Common Causes and Fixes

Downloading Your Filed Documents After Submission

Entering Foreign Currency Figures (Multi-Currency)

Entering Zero Figures: Why Fields Show as Blank

Filing a CT600 When Your HMRC Period Differs From Companies House

Filing CT600 After Submitting Accounts Separately

Filing CT600 and Companies House Accounts at the Same Time

Filing CT600 as a Tax Agent

Government Gateway and Corporation Tax Enrolment

How TinyTax Connects to HMRC and Companies House

How to Amend a CT600

How to file an amended CT600 when HMRC already has your return. Fix errors in figures, correct information, or respond to HMRC queries.

How to File a Dormant CT600

File your dormant company CT600 with TinyTax. Learn what counts as dormant, which fields to complete, and the difference between HMRC and Companies House dormancy.

How to Prepare Your Financial Figures for CT600 Filing

How Your CT600 Is Submitted to HMRC — Format and Verification

I Don't Have a UTR — Is My Company Registered for Corporation Tax?

Loss Carry-Back Claims

MTD for Corporation Tax — Quarterly Updates

Preview Is Not the Same as Submitting — How to Complete Your Filing

Clicking View Draft Submission generates a preview but does not file your return. Learn how to complete your CT600 and accounts submission.

Qualifying Charitable Donations and Box 305 on the CT600

R&D Tax Credits and TinyTax — What We File and What We Don't

R&D Tax Credits and TinyTax — What's Supported and What to Do

Understanding Your Tax Calculation

Understand how corporation tax is calculated from your accounting profit. Explains key CT600 boxes, disallowable expenses, capital allowances, and tax rates.

Unsupported Tax Features

TinyTax is designed for straightforward filings. Learn what advanced CT600 features aren't supported and how to work around limitations using existing fields.

Which CT600 Boxes Do Tax Adjustments Feed Into

Why Are Some CT600 Boxes Empty or Zero?

Explains why many CT600 boxes show as zero or empty in the preview. Covers which boxes apply to trading vs property companies, loss periods, and Box 3 (UTR).

Why Is the CT600 and Accounts Option Greyed Out?

Why Your HMRC Account Does Not Show Your Corporation Tax Filing Yet

Your First CT600 After Dormancy

Your first CT600 after dormancy covers a different period than you expect. Learn how CT600 periods work when transitioning from dormant to trading.

Troubleshooting CT600 Errors

Fix common TinyTax errors including HMRC Error 3001, authentication failures, invalid UTR, and Companies House auth code issues.

Fix CT600 Submission Errors

Fix CT600 submission errors quickly. Common error codes explained with step-by-step solutions for HMRC rejection issues.

Fix CT600 Authentication Errors

CT600 authentication failed when filing? Learn why HMRC rejects your credentials and how to fix authentication errors step by step.

Fix Government Gateway Login Errors

Can't log into Government Gateway? Fix common login errors including forgotten User ID, locked accounts, and authentication failures.

HMRC Error 1046: Authentication Failure Fix

Getting HMRC Error 1046 when filing your CT600? This guide explains why authentication fails and how to fix your Government Gateway credentials.

HMRC Error 1608: Invalid UTR Fix

Getting HMRC Error 1608 when filing CT600? This guide explains why your UTR is being rejected and how to fix the invalid UTR error.

HMRC Error 3001: Business Logic Failure Fix

Getting HMRC Error 3001 when filing CT600? Learn what causes this iXBRL validation error and how to resolve business logic failures.

CT600 Not Showing on HMRC Website

Fix Documents Out of Date Error Before CT600 Submission

How to Restore a Company You Removed from Your Dashboard

Troubleshooting HMRC Submission Errors

Troubleshooting Payment and Checkout Errors

Unable to Save: Session Data Missing — How to Fix

What Does a Disabled Period Mean?

Why Are the P&L Totals Showing the Wrong Amount?

Pricing and Plans

Which TinyTax plan is right for you? Compare Solo and Portfolio plans, billing, and what's included.

How Many Companies Can I File For? Portfolio Plans Explained

How to Upgrade Your Subscription Plan

Learn how to upgrade your subscription plan to file for more companies. Self-service upgrade with automatic proration.

VAT on TinyTax Invoices and Subscription Fees

What Happens After You Pay — Subscription Confirmation and Next Steps

When Does My TinyTax Subscription Start?

Billing, Pricing, and Cancellation

How billing works on TinyTax. Pay-per-filing pricing, refund policy, and cancellation.

Export Your Xero Trial Balance

Step-by-step guide to exporting your trial balance from Xero. Get your accounts ready for CT600 filing with TinyTax.

How to Import Your Trial Balance

How to import your trial balance into CT600 software. Speed up corporation tax filing by importing from Xero, QuickBooks, or CSV files.

Xero to CT600: Import Your Trial Balance

How to export your trial balance from Xero and import it into CT600 software. Step-by-step guide for faster corporation tax filing.

QuickBooks to CT600 Guide

How to export your trial balance from QuickBooks and import it into CT600 software. Step-by-step guide for UK corporation tax filing.

FreeAgent Category Mapping

How FreeAgent categories map to TinyTax's P&L fields. Includes trial balance import instructions.

FreeAgent to CT600 Guide

How to use FreeAgent accounts for your CT600 filing. Export your trial balance and complete your corporation tax return with TinyTax.

Sage to CT600 Guide

How to use Sage accounts for CT600 filing. Export your trial balance from Sage 50 or Sage Business Cloud and file with TinyTax.

Wave to CT600 Guide

How to use Wave Accounting for CT600 filing. Export your financial data from Wave and file your corporation tax return with TinyTax.

CT600 from Spreadsheets

How to file CT600 when you use Excel or Google Sheets for bookkeeping. Prepare your spreadsheet accounts for corporation tax filing.

Small Company Accounts (FRS 102 Section 1A)

How TinyTax automatically detects whether your company needs micro-entity or small company accounts, and what's different.

Micro-Entity vs Small Company Accounts

When does TinyTax use micro-entity (FRS 105) vs small company (FRS 102 Section 1A) accounts? Covers thresholds and auto-detection.

What Is a Confirmation Statement?

What is a confirmation statement? When it's due, what it contains, and how to file. Your guide to this annual Companies House requirement.

How to Strike Off Your Company

How to close your limited company by striking off. Understand the process, requirements, and alternatives to voluntary dissolution.

Companies House Auth Code

Find your Companies House Authentication Code for filing accounts. Learn where to locate it, how to request a new one, and fix common auth code errors.

Companies House WebFiling Service Ending — How to File Accounts

Dividends Paid — Where They Appear in Your Accounts

Downloading Your Accounts and Filing Documents from TinyTax

Entering Your Figures Without a Trial Balance

Filing LLP Accounts with Companies House

How to Amend Companies House Accounts

How to File Final Returns When Your Company Has Ceased Trading

Step-by-step guide to filing your final CT600 and accounts before dissolving your limited company. Learn how to set custom period dates for a shortened final return.

Negative Balance Sheet: What It Means and How to Enter the Figures

Overriding the Tax Charge in Your Income Statement (Deferred Tax)

What Gets Filed to Companies House

When Are Companies House Accounts Due? (9-Month Deadline Explained)

Why Are Prior Year Comparative Figures Showing as Zero?

Director Identity Verification for Confirmation Statements

How to file your confirmation statement (CS01)

How do I connect Xero?

How to Edit or Change Your Accounting Period Dates

How to enter custom accounting period dates when your CT603 shows different dates from the dropdown.