Professional accounting software for accountancy firms and SMEs: as an Official TeamSystem Partner, we implement Contasol, migrate your data from ContaPlus or other systems, and ensure your accounting operations run without interruption. With integrated SII and preparation for Verifactu ahead of the 2027 deadlines.
Contasol is the professional accounting software by TeamSystem (DELSOL brand), designed to manage complete bookkeeping for companies and client portfolios in accountancy practices. It handles journal entries, general ledger, periodic VAT and income tax filings, Corporation Tax, annual accounts, and operates with the Immediate Supply of Information system (SII) from the Spanish Tax Agency (AEAT) for companies required to use it. It is available in a free single-user version, a Standard plan (~€155/year indicative, as published by the manufacturer) and an Elite plan (~€415/year indicative), as well as a Cloud subscription from ~€21/user/month (market prices published by TeamSystem; always check the current pricing).
At Summum Sistemas we have been supporting companies and practices in the implementation and maintenance of management tools since 2007. We know the critical points of a Contasol rollout: configuring the chart of accounts, importing historical data without loss, setting up tax filing templates and integrating with Factusol or Nominasol when working within the DELSOL 360 suite. Our team resolves these scenarios without the practice having to figure it out on their own.
The deadline for adapting invoicing systems to Verifactu is approaching: legal entities must comply by 1 January 2027 and self-employed individuals by 1 July 2027 (RDL 15/2025). Contasol already includes the SII module; Verifactu compliance depends on the manufacturer and the installed version. If your business issues invoices from a system connected to Contasol, it is worth reviewing the actual invoicing workflow — Factusol, FactuGes or another tool — and planning the update with enough lead time. We audit your current installation and define the action plan before the deadline becomes critical.
We analyse the accounting software you use today (ContaPlus/Sage 50, a3CON, spreadsheets or other), the number of companies or financial years to migrate, the active tax filings and whether you already operate with SII. We identify migration risks and provide a realistic effort estimate.
We install Contasol on-premise or in the cloud depending on your working model, configure the chart of accounts tailored to your sector, define VAT groups, tax forms (303/115/190/200) and multi-user access where applicable. If you use Factusol or Nominasol, we integrate the data flow between applications.
We export the accounting history from your previous system, clean up inconsistencies and load the journal entries, chart of accounts and opening balances into Contasol. We verify that all balances reconcile before handing over the live environment.
We train the accounting team in day-to-day use: posting entries, generating tax returns, year-end closing and electronic filing. We review your invoicing workflow to confirm that Verifactu compliance is in place before the legal deadline, and we support you through future updates.
The operational detail: what we deliver as part of the work and what we keep alive afterwards.
Full Contasol implementation
Installation, chart of accounts configuration, VAT type setup, tax filing templates and user access profiles tailored to the practice or company.
Migration from ContaPlus / Sage 50 or other systems
Export, cleansing and loading of the accounting history (journal entries, chart of accounts, balances) with reconciliation checks before go-live.
SII configuration
Setup of the Immediate Supply of Information system for companies with turnover above €6M/year or otherwise required; testing against the AEAT web service.
Tax filings and annual accounts
Configuration and review of forms 303, 115, 130, 190 and 200 within Contasol; generation of balance sheet, P&L and notes for filing at the Companies Registry.
Integration with Factusol and Nominasol
Linking the invoicing flow from Factusol and payroll journal entries from Nominasol into Contasol, eliminating double data entry.
Ongoing support and Verifactu readiness
Support service for incidents, version updates and review of the invoicing workflow against the Verifactu deadline (legal entities: 1 January 2027; self-employed: 1 July 2027).
Contasol covers accounting; Summum Sistemas completes the picture with Factusol for invoicing and stock, Nominasol for payroll, and the DELSOL 360 cloud suite — and when the practice needs to automate document review workflows or deploy an accounting copilot, Summum IA steps in.
Factusol manages invoicing and stock; its sales and purchase data feed directly into Contasol to close the accounting cycle without double entry.
View service → sistemasComprehensive planning for Verifactu compliance: audit of the invoicing workflow, version updates and a compliance calendar ahead of the 2027 deadlines.
View service → iaCopilot for practices that automates the classification of accounting documents, review of recurring journal entries and drafting of reports based on Contasol data.
View service →They are separate but complementary products from TeamSystem/DELSOL. Factusol handles invoicing, stock control and purchase/sales management; it is NOT accounting software. Contasol provides full professional accounting: journal entries, accounting books, tax filings and annual accounts. Many companies use both in parallel, with Factusol data flowing into Contasol to close the cycle.
The AEAT does not approve or certify accounting or invoicing software. The current legal mechanism (RD 1007/2023) is the manufacturer's Declaration of Conformity, which certifies that the program meets the technical requirements of Verifactu. Contasol's SII module operates via the official AEAT web services. If you need documentary assurance about the compliance status of your installed version, we will review it with you.
This is the most common migration we handle. We export the history from ContaPlus (.bac or .txt format) or Sage 50, normalise the chart of accounts and load the journal entries into Contasol, verifying that balances reconcile before you start working in the new system. The process does not interrupt the practice's daily operations.
Under RDL 15/2025, legal entities must have their systems compliant by 1 January 2027 and self-employed individuals by 1 July 2027. If you issue invoices from a system separate from Contasol (for example, Factusol), that system is the one that must be Verifactu-compatible. We help you audit your actual invoicing workflow and plan the update with sufficient lead time.
Yes. We provide support for incidents, upgrades to new versions of Contasol and additional training when there are regulatory changes or staff turnover. As a consultancy with five offices in Castilla y León and the Canary Islands, we can assist you both remotely and on-site depending on the situation.