Best GST filing software for CA firms in India (2026): ClearTax, Tally, CompuGST, KDK, Saral, GSTZen and more compared

Quick answer. If your clients already keep books in TallyPrime, its connected GST features now cover upload, reconciliation and IMS actions, so a separate filing tool is optional for small practices. For a CA office filing for dozens of GSTINs, the established desktops are CompuGST, Winman and Saral, with KDK’s Spectrum and ExpressGST as the cloud, multi-user option. ClearTax and Cygnet are enterprise GSP suites bought on the client’s licence. GSTZen is the metered, pay-per-API-call outlier. Firms above about 100 GST clients increasingly keep one of these for filing and add custom automation for the reconciliation, IMS and supplier chasing that none of them finish.

Prices below are from vendor pages as of October 2026, excluding GST unless stated. Several vendors publish nothing and quote on request; we say so rather than guess.

How we compared

GST filing for a CA office breaks into five jobs: getting data out of client books, preparing GSTR-1 and GSTR-3B for many GSTINs, reconciling GSTR-2B and the Invoice Management System against purchase registers, acting on IMS before the 14th, and filing through either a GSP connection or the portal’s offline tool. We rated tools on how many of those five they do without a human re-keying and on fit for a 5 to 25 partner firm.

Comparison table

GSP connection or manual upload

Every tool here files the same return data. What differs is the path to the portal. GSTN empanels GST Suvidha Providers, 62 companies after the fifth batch including ClearTax, Tally, Zoho, Cygnet and Masters India, who connect to GSTN APIs on your behalf. A GSP-connected tool asks you to enable API access on the portal and confirm by OTP, then pulls GSTR-2B, IMS records and filing status for every GSTIN in one run.

The alternative is the free route: prepare data in the Returns Offline Tool, generate a JSON file, log in per GSTIN and upload under Prepare Offline. GSTN’s own FAQ says a file of up to 10,000 line items uploads in one go and that re-uploads overwrite earlier data until the return is filed with DSC or EVC (GSTN offline tool manual). For IMS, GSTN added an Excel-based IMS offline tool in April 2026. The manual route works; it just costs a login, an OTP and a JSON per client per return. Tools that ask for the client’s portal password instead of API consent are scraping, and we would not use them.

The tools in detail

ClearTax GST

The broadest enterprise suite. Its enterprise page lists GSTR-1 to GSTR-9 filing on an ASP/GSP connection, PAN-level matching across multiple GSTINs and one-click bulk downloads of filed returns for all GSTINs (ClearTax enterprise GST). A January 2026 release added an IMS console with pending actions, remarks and ITC-reversal declarations. Pricing is contact-sales. A professionals’ Expert Pack for up to 300 GSTINs, 3,000 invoices per GSTIN and 5 users is listed publicly, but the page shows a dollar figure we could not confirm, so treat it as on request. Most CA firms meet ClearTax on a large client’s licence rather than their own.

Zoho Books

Not a CA practice tool, but worth knowing because clients bring it. The India pricing page runs from Standard at ₹899 per organisation per month (₹749 on annual billing) to Ultimate at ₹9,599 (₹7,999 annual), with a free plan while revenue stays under ₹25 lakh; GST filing is included from the free tier and e-invoicing from Standard (Zoho Books pricing). Zoho’s help documents cover GSTR-2B reconciliation and IMS actions pushed back to GSTN once API access is enabled. Because pricing is per organisation, it does not scale as a firm-wide filing desk.

TallyPrime

The ledger most clients already run, now with connected GST: Tally’s feature page describes downloading and auto-reconciling GSTR-2A and 2B, bulk accept, reject and pending actions for IMS, uploading GSTR-1 and filing and signing returns from inside the product (TallyPrime taxation features). Licences are ₹22,500 for Silver and ₹67,500 for Gold, one-time, with the TSS subscription that keeps connected services alive at ₹4,500 or ₹13,500 a year plus GST (Tally cost of ownership guide, TSS renewal). The limit is that each client’s Tally is its own island; there is no cross-client view of who is unfiled.

CompuGST (CompuTax)

The GST module of the CompuOffice suite. Its product page lists bulk return filing, multiple GSTINs, offline preparation of all returns, automatic fetching of counterparty GSTR data for comparison with accept and reject actions, and Tally and Excel import (CompuGST product page). The vendor publishes no price; reseller listings hover around ₹7,500 a year, so ask for a quote. It remains the default for firms that live in CompuTax for ITR and TDS.

Winman GST

Winman’s site lists Tally and Excel import, automatic sorting of sales into B2B and B2CS, automatic GSTR-2A and 2B reconciliation, carry-forward of pending 2B invoices to the next month and annual summaries for GSTR-9 (Winman). Pricing is not published. It makes sense for offices already paying for Winman CA-ERP.

KDK Spectrum and ExpressGST

KDK sells the Spectrum suite and a cloud GST product, ExpressGST, whose menu advertises an IMS console, smart reconciliation and PAN-level filing. The clearest public price is the ICAI member scheme: a pack of 500 returns for ₹1,800 plus GST with unlimited users, plus a free first year covering 100 filings (ICAI beneficiary scheme). Marketplace listings put Spectrum at about ₹6,300 per user per year; the vendor quotes on request. The right pick when partners and staff file from different offices.

Saral GST

Relyon publishes prices, which is rare in this category: Saral GST Standard at ₹7,620 for a single user and ₹16,800 for multi-user, plus 18% GST, with unlimited companies, GSTR comparison and ITC set-off; the Premium edition adds e-invoicing on a custom quote (Saral GST pricing).

GSTZen

The only metered option. The tax consultant plan is a prepaid wallet with unlimited GSTINs, charged at ₹5 per API call; GSTZen’s own examples put a monthly GSTR-1 filing at about 7 calls (₹35) and a GSTR-3B at about 5 calls (₹25) (GSTZen consultant pricing). Per-GSTIN taxpayer plans run ₹5,250 to ₹8,000 a year plus GST, and 2B reconciliation works through Excel or Tally (GSTZen 2B reconciliation). Cheap for small, predictable volumes; model the call count before committing.

Cygnet Tax

A GSTN-approved GSP and IRP in one vendor, combining return filing, AI reconciliation, e-invoicing and e-way bills with ERP connectors (Cygnet indirect tax). Pricing is on request and the product is sized for corporates.

Custom AI automation

Every tool above prepares and files. None finish the monthly loop for a firm with 150 clients: matching 2B and IMS against each client’s purchase register with that client’s tolerance rules, proposing accept, reject and pending actions before the 14th, chasing the suppliers who have not filed, and flagging Rule 37A exposure. A custom system does exactly that across whichever ledgers and filing tools the firm already has, on a fixed-fee prototype and then a retainer. This is what we build at DotZero; the accounting automation page explains the scope and the live demo runs a reconciliation on sample data. It is one option, not a replacement for a filing suite.

Who should pick what

• Sole proprietor, under 50 GSTINs: clients’ Tally with connected GST, plus Saral GST or the KDK ICAI pack for the clients not on Tally. Under ₹15,000 a year.
• 5 to 10 partner firm, 100 to 400 GSTINs: CompuGST or Winman if you already own the suite, KDK ExpressGST if staff are spread across offices, and a reconciliation and chasing layer, custom or otherwise, because the 12th to 14th window is where the hours go.
• Firm with enterprise clients: work on the client’s ClearTax or Cygnet licence; do not buy enterprise seats for a practice.

What changed in 2025 and 2026

Three rule changes decide which features matter. First, auto-populated liability in GSTR-3B became non-editable from the July 2025 tax period, with corrections routed through GSTR-1A (GSTN advisory, 7 June 2025), so GSTR-1 accuracy is now the whole game. Second, returns more than three years past their due date are barred on the portal from the November 2025 tax period (GSTN advisory, 29 October 2025). Third, IMS makes inaction a decision: records with no action are deemed accepted when the draft GSTR-2B is generated on the 14th, any action after that requires a recompute, and GSTR-2B is now sequential, generated only once the previous period’s GSTR-3B is filed (GSTN IMS advisory). From the October 2025 tax period, credit notes can be kept pending for one tax period and the recipient declares how much ITC to reverse (GSTN IMS FAQ, October 2025).

When you evaluate a vendor, ask when they shipped each of those. For the wider office stack, see our best software for CA offices comparison; for the reconciliation mechanics behind the 14th, read GSTR-2B reconciliation in 2026.