Base Segment: The Backbone of Each Tradeline

Purpose

The base segment contains the core attributes for a trade: portfolio and account type, key dates, balances, account status, and optional history. Appendage segments add context that applies only to specific scenarios.

Minimal viable set

Start with a minimal, consistent subset: identification values (furnisher/branch, account number), core classification (portfolio + account type), pivotal dates (opened, as-of), balance amounts, and current status.

Treat these fields as a coherent snapshot for a single cycle; avoid mixing values from different statement dates, which creates internal contradictions and downstream edits/rejects.

Common mistakes and quick fixes

Reporting a past-due amount while status is current or paid. Fix by zeroing the past-due when status indicates 0–29 days late or paid/closed.

Leaving stale as-of dates. Fix by ensuring the as-of date advances each cycle and matches the source-of-truth cutoff.

Changing account numbers without L1 lineage. Fix by using L1 to preserve continuity and consumer understanding.