Two tax systems. One workspace.
Most platforms assume your client files in one country. We assume they don’t — MJDS spread carry, treaty withholding, superficial-loss vs wash-sale, flow-through credits, NR-301 and Form 1116, computed for the right passport.
What a cross-border tax pro gets.
US-only tools quietly break every Canadian tax mechanic. We file in both.
Treaty-Aware Withholding
Canada-US treaty rates, NR-301 and Form 1116 foreign-tax-credit mechanics — the right number for the right passport, every time.
treaty · NR-301 · 1116Superficial-Loss vs Wash-Sale
The 30-day rules differ across the border — track both so a client’s loss isn’t quietly denied on the wrong side.
both 30-day rulesFlow-Through & MJDS
Flow-through share credits, MJDS spread carry, and dual-listed FX-adjusted cost base — the CA-specific mechanics US tools break.
FTS · MJDS · FXDual-Filing Evidence
SEC EDGAR unified with the MJDS 40-F / F-10 cross-border record and SEC Form 4 insider transactions — each cited to the filing it came from, for the working paper.
EDGAR · MJDS 40-F · Form 4Built for clients who don’t file in one country.
Stop rebuilding cross-border mechanics in a spreadsheet. Start free — 30 Quinn queries a month, no card.
Calculators you can use before signing up
Cross-border tax and superficial-loss checks, computed in your browser. Nothing is saved and no sign-in is required. These are calculation tools, not advice.