RentalBux vs. SliQ Invoicing
Which MTD Software Is Better for UK Landlords and Sole Traders?
Overall Winner: RentalBux
RentalBux is the more complete MTD software for landlords and sole traders. It combines full Making Tax Digital compliance across UK property income, foreign property income, and self-employment income with comprehensive property management, automated bookkeeping, AI-driven expense categorisation, joint ownership profit-splitting, and a free plan for single-property landlords until March 2028. SliQ Invoicing is a capable Windows-based desktop invoicing and billing application with HMRC-recognised MTD for Income Tax quarterly submission support, but it is currently limited to self-employment income only — property businesses and end-of-year submissions (Final Declaration) are not supported. This makes SliQ unsuitable as standalone MTD software for landlords.
At-a-Glance MTD Software Comparison
Key differences between RentalBux and SliQ Invoicing across MTD compliance, property management, bookkeeping, pricing, and landlord-specific features.
| Feature | RentalBux | SliQ Invoicing |
|---|---|---|
| Software Type | Property/Landlord Platform | Desktop Invoicing Application (Windows) |
| Target Users | Landlords, Sole Traders, Letting Agents | Self-Employed, Small Businesses (trades, services) |
| Income Sources Supported | Sole Trader + UK Property + Foreign Property | Self-Employment only (property not supported) |
| Free MTD Software Plan | Free until March 2028 (1 property) | Free trial (paid licence: £54.99/year) |
| MTD Quarterly Updates to HMRC | Yes | Yes |
| Final Declaration | Yes | No |
| Bank Reconciliation | Yes | No |
| Automated Bank Feeds | Yes | No |
| Invoice Creation | Yes | Yes |
| Receipt Capture (OCR) | Yes | No |
| Expense Auto-Categorisation | Coming soon | No |
| Property Portfolio Management | Yes | No |
| Tenant Management | Yes | No |
| Joint Ownership & Profit Sharing | Yes | No |
| Payroll | No | No |
| HMO Unit-Level Tracking | Yes | No |
| HMRC SA105 Box Pre-Mapping | Yes | No |
| Spreadsheet Import/Export | Yes | No |
| Platform | Web, iOS, Android | Windows desktop application, Server mode, Online/cloud version |
| GDPR Compliant | Yes | Yes |
What Is RentalBux? What Is SliQ Invoicing?
What Is RentalBux?
All-in-One MTD Software for Landlords and Sole Traders
RentalBux is an all-in-one property management, accounting, and Making Tax Digital compliance platform built specifically for UK landlords, letting agents, and self-employed individuals. Designed with direct input from accountants who specialise in property and sole trader tax, RentalBux covers everything from tenancy management and rent collection to full bookkeeping with a pre-configured chart of accounts tailored to the property sector.
RentalBux is fully HMRC-recognised for Making Tax Digital for Income Tax across all three qualifying income categories: UK property income, foreign property income, and self-employment. This makes it one of the only landlord-specific MTD software platforms that can handle a landlord who also runs a sole trader business, all from a single subscription.
A major differentiator is RentalBux's pricing model: single-property landlords can use the platform completely free until March 2028, making it one of the most affordable HMRC-approved MTD software options for landlords entering the MTD regime.
What Is SliQ Invoicing?
SliQ Invoicing is a Windows desktop invoicing application developed by SliQTools, a UK software company based in Shrewsbury, Shropshire, that specialises in business software for small to medium-sized companies. SliQ's primary function is creating and tracking professional invoices, credit notes, purchase orders, delivery notes, quotes, and customer statements. It also lets users record supplier bills and track payments, with stock control features for inventory management. The software includes a customisable template editor for designing invoice layouts with logos, graphics, and custom fields.
SliQ Invoicing is HMRC-recognised for both MTD for VAT and MTD for Income Tax. For VAT, SliQ provides a wizard that steps users through authorising the software, viewing VAT obligations, and submitting VAT returns directly to HMRC. For MTD ITSA, SliQ supports quarterly submissions to HMRC for self-employed people — however, end-of-year submissions (Final Declaration) and property businesses are not currently supported. This is a critical limitation for landlords: SliQ cannot be used as standalone MTD software for rental property income.
Strengths
- Free MTD software for single-property landlords until March 2028
- Handles sole trader + UK property + foreign property income in one platform
- Joint ownership with automatic profit-sharing split by ownership percentage
- Pre-built chart of accounts tailored for landlords and sole traders
- AI-powered expense auto-categorisation and OCR receipt capture
- Agent filing on behalf of landlords — ideal for accountants and letting agents
- Supports HMO properties with auto-created units
Strengths
- HMRC-recognised for MTD ITSA (quarterly self-employment updates)
- HMRC-recognised for MTD for VAT (full VAT return submission)
- Strong invoicing with customisable templates, quotes, credit notes
- Includes stock control and purchase orders
- Records supplier bills and tracks business expenditure
- Client/server mode for multi-user shared access
- One-time annual fee of £54.99/year — no monthly subscription
- Domestic VAT Reverse Charge and Northern Ireland Protocol support
- Established product with positive user testimonials
Limitations
- Newer to market compared to established platforms
- No yield or LTV investment analysis tools
- No MTD for VAT support yet
- Some advanced reporting features still in development
- Limited third-party app integrations
- No offline capability
- No tax liability forecasting feature currently
Limitations
- Property income NOT supported for MTD ITSA
- Final Declaration / end-of-year submissions NOT supported
- Windows desktop only — no web, iOS, or Android access
- No bank feeds, no open banking, no automated reconciliation
- No AI-powered features, no OCR receipt capture
- No property portfolio management, tenant tracking, or rent tracking
- No chart of accounts, no journal entries, no formal P&L
- No agent filing on behalf of landlord clients
- No cloud storage — data stored locally on Windows PC
Making Tax Digital Compliance
How RentalBux Handles MTD Compliance
RentalBux supports all three MTD qualifying income categories: sole trader income, UK property income, and foreign property income. This makes it suitable for landlords who also earn self-employment income, eliminating the need for separate software. Most accounts are pre-mapped to HMRC Self-Assessment boxes. RentalBux also supports agent filing, allowing accountants or letting agents to submit MTD returns on behalf of their landlord clients.
How SliQ Invoicing Handles MTD for Sole Traders (Not Landlords)
SliQ Invoicing is HMRC-recognised for MTD ITSA but with significant limitations. The platform supports quarterly submissions to HMRC for self-employed people only. Property businesses are not currently supported — meaning landlords cannot use SliQ to submit quarterly updates for rental income. Additionally, SliQ does not support end-of-year submissions (the Final Declaration that replaces the traditional Self Assessment tax return). Users must continue to use a bookkeeper or accountant for end-of-year submission. SliQ provides an easy-to-use wizard for the quarterly submission process: authorising SliQ to submit on your behalf, viewing obligations from HMRC, reviewing cumulative income and expense figures, and submitting them. For MTD for VAT, SliQ provides full support including viewing obligations, calculating VAT on sales and purchases, and submitting VAT returns.
| Feature | RentalBux | SliQ Invoicing |
|---|---|---|
| HMRC Recognised (MTD ITSA) | Yes | Yes |
| MTD Quarterly Updates | Yes | Yes |
| Final Declaration | Yes | No |
| Digital Record Keeping | Yes | Yes |
| Digital Links Compliant | Yes | Yes |
| Sole Trader Income | Yes | Yes |
| UK Property Income | Yes | No |
| Foreign Property Income | Yes | No |
| Multiple Income Streams | Yes | No |
| Agent Filing on Behalf | Yes | No |
Winner: RentalBux — This is a decisive difference. RentalBux covers all three MTD income types and supports the full MTD lifecycle including quarterly updates and the Final Declaration. SliQ Invoicing only handles self-employment quarterly updates — property income is not supported, the Final Declaration is not supported, and landlords cannot use SliQ as their MTD software for rental income.
Property Management
RentalBux: Property Management
RentalBux provides comprehensive property portfolio management with tenant management, rent tracking, property expense allocation, and support for multiple properties. A standout feature is its joint ownership and profit-sharing capability: landlords can define ownership percentages once, and RentalBux automatically splits rental income and expenses. RentalBux also supports HMO properties, automatically creating individual units.
SliQ Invoicing: No Property-Specific Features
SliQ Invoicing does not offer any property-specific features. There is no property portfolio management, no tenant management, no rent tracking, no per-property expense allocation, no joint ownership automation, no HMO support, and no compliance document alerts. SliQ is designed for businesses that invoice customers for goods and services — not for managing rental property portfolios. Even if a landlord wanted to use SliQ for basic record keeping, the software cannot submit property income to HMRC under MTD.
| Feature | RentalBux | SliQ Invoicing |
|---|---|---|
| Property Portfolio Management | Yes | No |
| Tenant Management | Yes | No |
| Rent Tracking | Yes | No |
| Property Expense Allocation | Yes | No |
| Multiple Property Support | Yes | No |
| HMO Property Support | Yes (auto-creates units) | No |
| Joint Ownership/Profit Sharing | Yes (auto-split by %) | No |
| Maintenance Tracking | No | No |
| Tenant Screening | No | No |
| Compliance Document Alerts | Yes | No |
| Arrears Tracking | No | No |
Winner: RentalBux — SliQ Invoicing has zero property management features and cannot submit property income under MTD. This category is entirely one-sided.
Bookkeeping, Accounting & Digital Record Keeping
RentalBux: Structured Accounting
RentalBux includes a pre-built chart of accounts specifically designed for landlords and sole traders, covering rental income, mortgage interest, insurance, property repairs, professional services, utilities, and tenant deposits. All accounts are pre-mapped to HMRC Self-Assessment boxes. The platform supports cash basis accounting, bank reconciliation, and journal entries.
SliQ Invoicing: Invoice and Bill Tracking with Sales vs Expenditure Reports
SliQ Invoicing provides digital record keeping through its invoicing and billing system. Users raise invoices for income, record supplier bills for expenses, and track customer payments. Bill items can be categorised to see where money is being spent. The software provides reports on sales, payments, customers, and suppliers, giving a view of business performance including sales versus expenditure. However, SliQ does not offer a chart of accounts, journal entries, double-entry bookkeeping, bank reconciliation, automated bank feeds, or open banking integration. All data entry is manual — there is no way to automatically import bank transactions.
| Feature | RentalBux | SliQ Invoicing |
|---|---|---|
| Cash Basis Accounting | Yes | |
| Chart of Accounts (Pre-built, Landlord-Tailored) | Yes (pre-built + custom) | No |
| Journal Entries | Yes | No |
| Bank Reconciliation | Yes | No |
| Automated Bank Feeds | Yes (Major UK banks) | No |
| Open Banking Integration | Yes | No |
| Double-Entry Bookkeeping | Yes | No |
| HMRC Box Pre-Mapping | Yes | No |
| Xero Integration | No | No |
| Spreadsheet Import/Export | Yes | No |
| Digital Record Storage | Yes | Yes |
Winner: RentalBux — The pre-built landlord chart of accounts, journal entries, double-entry bookkeeping, automated bank feeds, and open banking give RentalBux a structured accounting foundation that SliQ lacks entirely. SliQ provides basic invoice and bill tracking with category-level reporting, but no formal accounting structure.
Invoicing, Expense Tracking
RentalBux: Expense Management
RentalBux includes OCR receipt capture, structured expense tracking with landlord-specific categories, auto-categorisation, invoice creation with customisable branding, and payment tracking with reminders.
SliQ Invoicing: Full-Featured Invoicing with Template Editor
SliQ Invoicing is a dedicated invoicing platform with extensive capabilities. It offers multiple customisable invoice templates with a built-in template editor for adding logos, graphics, text, and custom fields. Users can create invoices, quotes/estimates, credit notes, purchase orders, delivery notes, and customer statements. The software supports recurring invoices for automated monthly billing, email templates for sending invoices with formatted HTML, and PayPal button integration for faster payment. Stock control features help track inventory levels with a reorder wizard. However, SliQ has no AI-powered features, no OCR receipt capture, no automated expense categorisation, and all data entry is manual.
| Feature | RentalBux | SliQ Invoicing |
|---|---|---|
| Invoice Creation & Sending | Yes | Yes |
| Invoice Customisation/Branding | Yes | Yes |
| Online Payment Collection | Yes | Yes |
| Payment Tracking/Reminders | Yes | Yes |
| Expense Tracking | Yes | Yes |
| Receipt Capture (OCR/Photo) | Yes | No |
| Expense Categorisation | Yes | Yes |
| Automated Transaction Matching | Yes | No |
| Mileage Tracking | No | No |
| AI Auto-Categorisation | Coming soon | No |
Winner: RentalBux for landlord expense management. RentalBux wins on expense management with OCR receipt capture and landlord-specific categorisation — features that matter more for property income under MTD.
Reporting & Tax Forecasting
RentalBux: Formal Accounting Reports
RentalBux produces structured financial reports including profit & loss statements, balance sheets, journal reports, ledger reports, and trial balances. Smart categorisation helps ensure accuracy.
SliQ Invoicing: Sales and Business Performance Reports
SliQ Invoicing provides numerous reports on sales, payments, customers, and suppliers. Users can view a summary of their business including sales versus expenditure, which provides a basic view of business performance. Custom reports can be created. However, SliQ does not produce formal profit & loss reports, balance sheets, trial balances, or per-property financial breakdowns. There is no real-time dashboard and no tax forecasting capability.
| Feature | RentalBux | SliQ Invoicing |
|---|---|---|
| Profit & Loss Report | Yes (formal) | No |
| Balance Sheet | Yes | No |
| Trial Balance | Yes | No |
| Dashboard/Overview | Yes | No |
| Real-Time Financial Data | Yes | No |
| Cash Flow Reporting | No | No |
| Tax Estimate/Forecast | Yes | No |
| AI-Powered Features | Coming soon | No |
Winner: RentalBux — RentalBux leads on formal accounting reports (P&L, balance sheet, trial balance, per-property reporting). SliQ provides useful sales and payment reports for invoicing businesses but no structured accounting statements.
Collaboration & Mobile Apps
RentalBux's Collaborative Features
RentalBux enables agent filing, which gives accountants and letting agents the ability to submit directly on a landlord's behalf.
SliQ Invoicing: Windows Desktop with Client/Server Mode
SliQ Invoicing is a Windows desktop application — it runs only on Windows PCs and has no web browser access, no iOS app, and no Android app. Data is stored locally on your hard drive. However, SliQ does offer a client/server mode that allows multiple users to work on the same company data simultaneously, sharing invoice templates and attachment data. This is useful for small businesses with multiple staff members who need to raise invoices. SliQ does not offer an accountant portal or agent filing. Support is available via email only; there is no phone support.
| Feature | RentalBux | SliQ Invoicing |
|---|---|---|
| Accountant/Advisor Portal | Yes | No |
| Multi-User Access | Yes | Yes |
| Agent Filing on Behalf | Yes | No |
| Bank Integration | Yes | No |
| Platform | iOS, Android | Windows desktop application, Server mode, Online/cloud version |
| Web Browser Access | Yes | No |
| FCA Regulated | Yes | No |
| GDPR Compliant | Yes | Yes |
Winner: RentalBux — Cloud-based access from any device, dedicated mobile apps, agent filing on behalf, and an accountant portal make RentalBux dramatically more accessible and collaborative than SliQ's Windows-only desktop application. SliQ's client/server mode provides basic multi-user capability but lacks the flexibility of cloud-based access.
Ease of Use, Support & Security
RentalBux: Guided Workflows
RentalBux uses guided workflows, clear dashboards, and no accounting jargon. The platform offers phone support, email/chat support, and a help centre with guides and knowledge base articles.
SliQ Invoicing's Ease of Use
SliQ Invoicing emphasises simplicity — users can produce their first invoice within minutes with no special accounting knowledge needed. The software uses wizard-based interfaces for MTD submissions, stepping users through each stage clearly. Customer testimonials praise SliQ's intuitive design and ease of flow. Support is available via email only (sales@sliqtools.co.uk). SliQ stores data locally on your Windows PC with no cloud backup — users are responsible for their own data backups. The optional client/server mode allows shared access on a local network.
| Feature | RentalBux | SliQ Invoicing |
|---|---|---|
| Phone Support | Yes | No |
| Chat Support | Yes | No |
| Email Support | Yes | Yes |
| Help Centre/Knowledge Base | Yes | Yes |
| FCA Regulated | Yes | No |
| Enterprise-Grade Security | Yes | No |
RentalBux Features
Sole Trader Income Support for MTD
RentalBux is one of the few landlord-focused MTD software platforms that supports self-employment income alongside UK and foreign property income within a single account. Landlords who also run a trade, consultancy, or freelance business can manage all quarterly submissions from one dashboard. Landlord Studio covers property income only.
Custom Chart of Accounts for Landlords
A property-tailored chart of accounts covering rental income, mortgage interest, insurance, repairs, utilities, letting agent fees, and more — all pre-mapped to HMRC Self-Assessment boxes. No setup required; the system is ready to use from day one. Landlord Studio has no equivalent.
Agent Filing on Behalf of Landlords
Letting agents and accountants can submit MTD quarterly updates and the Final Declaration on behalf of landlord clients directly from the platform. Landlord Studio allows accountant access but does not support submission on the landlord's behalf.
Branded Invoice Creation
Invoice creation with customisable branding for service charges and commercial landlords. Not available in Landlord Studio.
AI-Powered OCR Receipt Capture with Auto-Categorisation (Coming soon)
RentalBux's AI will read uploaded receipts and categorise the expense automatically against the pre-built chart of accounts. Landlord Studio's Smart Scan extracts dates and amounts but does not include AI-driven expense categorisation.
Formal Accounting Reports
Balance sheet, trial balance, ledger reports, and journal reports. Landlord Studio does not produce these natively.
Free Plan Including MTD Submissions Until March 2028
RentalBux's free single-property plan includes MTD quarterly submissions. Landlord Studio's free GO plan covers property management for up to three units but requires a paid PRO plan (from £12/month) to access MTD submission functionality.
Unique Features Only SliQ Invoicing Offers
MTD for VAT with Full Return Submission
SliQ is HMRC-recognised for MTD for VAT, with a wizard-guided process for viewing obligations, calculating VAT from sales and purchases, and submitting VAT returns directly to HMRC. The platform supports Domestic VAT Reverse Charge, Postponed VAT Account, and Northern Ireland Protocol requirements.
Quotes, Estimates & Credit Notes
SliQ creates professional quotes and estimates for potential customers, which can be converted to invoices. Credit notes can be issued for returns or adjustments. These are essential for trades businesses but not typically needed by landlords.
Purchase Orders & Delivery Notes
SliQ generates purchase orders for suppliers and delivery notes for shipments — features designed for product-based businesses and tradespeople.
Stock Control with Reorder Wizard
SliQ includes inventory tracking with stock level monitoring and a wizard to identify and reorder low stock items. This is valuable for businesses selling physical products but irrelevant for landlords.
Customisable Invoice Template Editor
SliQ's template editor allows users to modify invoice layouts with logos, graphics, text, custom fields, and column configurations. Multiple templates can be saved for different document types.
Recurring Invoices for Automated Billing
SliQ supports automated recurring invoices for regular monthly billing — useful for subscription businesses or regular service providers.
Client/Server Mode for Local Network Sharing
SliQ allows multiple users on the same local network to access and work on company data simultaneously. This is useful for small offices with multiple staff members raising invoices.
Who Should Choose RentalBux?
RentalBux is a strong fit if you:
Landlords with Mixed Income Streams
If you earn from both property and self-employment, RentalBux handles sole trader income alongside UK and foreign property income in a single MTD-compliant platform.
Joint Owners and Family Portfolios
The automated profit-sharing split is a standout feature. Define ownership percentages once and RentalBux calculates each owner's share automatically.
Budget-Conscious Landlords Entering MTD
Free MTD software for single-property landlords until March 2028, with no upfront commitment.
Landlords Who Want Proper Accounting Structure
Chart of accounts, journal entries, profit & loss, balance sheet, and trial balance give RentalBux a structured accounting foundation.
Accountants and Letting Agents
Agent filing on behalf, multi-user access, and spreadsheet import make RentalBux practical for professionals managing multiple landlord portfolios.
Commercial Landlords and HMO Owners
Invoice creation with branding for service charges, plus automatic HMO unit creation and tenant management.
Who Should Choose SliQ Invoicing?
SliQ Invoicing is the better choice for:
Self-Employed Tradespeople Who Need Professional Invoicing
If you're a builder, decorator, plumber, electrician, or other tradesperson who needs to create professional invoices, quotes, credit notes, and track customer payments, SliQ's dedicated invoicing features are comprehensive and well-designed. The customisable template editor lets you create branded documents that match your business identity.
Product-Based Small Businesses Needing Stock Control
If you sell physical products and need to track inventory levels, SliQ's stock control features with the reorder wizard are a genuine advantage that most MTD-focused platforms do not offer.
VAT-Registered Sole Traders Needing MTD for VAT
SliQ provides full MTD for VAT support including Domestic Reverse Charge and Northern Ireland Protocol. If your primary need is VAT return submission alongside invoicing, SliQ covers both.
Self-Employed Sole Traders with Simple MTD ITSA Needs
If you're self-employed (not a landlord), have straightforward income and expenses, and only need to submit MTD quarterly updates — with your accountant handling the end-of-year Final Declaration — SliQ can serve as your in-year MTD tool.
Businesses That Prefer Desktop Software Over Cloud
If you prefer to keep data on your own computer rather than in the cloud, and you work exclusively on Windows, SliQ's local installation with optional server sharing may appeal.