1) Executive Summary

The GST Reconciliation Tool is a unified, high-accuracy reconciliation and compliance engine designed to streamline GST-related validations across Books, GSTR-2B, GSTR-1, and E-way Bill datasets. It ingests multiple formats, auto-maps columns, normalizes invoice structures, and produces audit-ready mismatch reports, analytics dashboards, and consolidated GST working papers.

Core Outcomes:

- Rapid identification of GST mismatches (Books vs 2B, Sales vs GSTR-1, 3-way with E-way Bill)

- Automated compliance checks for Rule 37A, RCM indicators, blocked ITC, 16(4) time-bar

- Inbuilt review trail through notes, overrides, and downloadable progress files

- Comprehensive Excel/JSON export for working-paper documentation

2) Problem Statement

Organizations face challenges due to volume, inconsistent file formats, timing differences, reporting errors, and multiple GST data sources. Manual reconciliation is slow and manually intensive.

3) Target Users & Personas

- Audit Managers & Article Assistants

- GST & Compliance Teams

- CFOs and Controllers

- Internal Audit & Risk Teams

4) Data Inputs & Processing

Supported Inputs: Books, GSTR-2B, GSTR-1, Sales Register, E-way Bills, TDS data, turnover sheets, progress files.

Processing Includes:

- Intelligent column mapping

- Normalization of invoice numbers, GSTINs, dates, credit note adjustments

- Vendor name harmonization

- Categorization of mismatches

- Storage of overrides and notes

5) Functional Modules

Purchase Reconciliation, Sales Reconciliation, E-way Bill Reconciliation, Rule 37A, Composite Reconciliation, Dashboards & Analytics.

6) User Journey

Upload → Auto-map → Normalize → Reconcile → Review → Overrides → Analyze → Export.

7) Regulatory Mapping

Rule 37A, Sec 16(4), Sec 17(5), RCM categories, E-way bill requirements.

8) Business Value & KPIs

- >80% reduction in reconciliation time

- Improved mismatch visibility

- Standardized logic

- Audit-ready documentation exports

9) Technical Architecture

Streamlit-based, Polars/DuckDB ingestion, session persistence.

10) Differentiators

Multi-layer reconciliation engine, override-aware workflows, high performance, export-ready outputs.

11) Limitations

Mapping accuracy depends on input quality; vendor consolidation may require review.

12) Governance

Maker-checker workflows, override tracking.

13) Roadmap

Automated 3B builder, anomaly detection, TDS matching engine, policy-based rule engine.

14) Sample Scenarios

Examples of mismatches, missing invoices, anomalies, and Rule 37A flags.

15) Conclusion

A structured, law-aligned reconciliation framework enhancing accuracy, transparency, and efficiency

across GST reviews.