Field Manual · Revised October 2026
The December 31st Protocol
The 90-Day Countdown to Spain's Unforgiving Midnight Snapshot
The December 31st Protocol is a field manual for filing Spain's Modelo 721 — the annual declaration of crypto held with foreign custodians above €50,000. It covers the ninety-day countdown, the post-MiCA CNMV situs matrix, the snapshot valuation engine, and the Sede Electrónica walkthrough. Written for Spanish tax residents with foreign crypto positions, with three case files and three appendices.
- Length
- 84 Pages
- Revised
- Oct 2026
- Format
- Delivery
- Instant link
Why this manual exists
There is a specific kind of silence at 23:59:59 on the thirty-first of December. In that second, the Hacienda takes a photograph. Most people do not know the photograph is being taken. Fourteen months later, they receive a letter that begins with the word requerimiento.
What this guide solves
The 90-day countdown. D-90 to J-0, with five concrete waypoints. Full inventory, Cl@ve PIN, dry-run snapshot, freeze date, evidence capture. Miss two waypoints and you are filing at risk.
The CNMV situs matrix. Post-MiCA (July 1st, 2026), the domestic/foreign map was redrawn. Binance is no longer a straightforward domestic custodian. Bit2Me, Openbank, BBVA, and Cecabank are. Chapter 2 tells you which assets count toward the €50,000 threshold.
The correction protocol. The 90-day grace window. Three scenarios, three penalty regimes. File early, review, correct before March 31st, pay zero.
“The mirror is held up whether you look at it or not.”
— Salah Nomad
Inside the manual
- 1
The Midnight Mirror
The snapshot that does not wait for you. Penalty anatomy. The grace window.
- 2
The Geography Decision
Post-MiCA situs matrix. CNMV registry. The moving-asset caveat.
- 3
The 90-Day Countdown
D-90 to J-0. Inventory, Cl@ve, dry-run, freeze, evidence capture.
- 4
The Cl@ve and Sede Walkthrough
FNMT vs Cl@ve PIN. Decision matrix. The bottleneck nobody warns about.
- 5
The Snapshot Valuation Engine
Spot price vs FIFO. Three sources. The spreadsheet structure.
- 6
The Filing Ritual
The Sede, field by field. Seven checkpoints. Saving draft vs submitting.
Show the other 5 chapters
- 7
The Correction Protocol
Three scenarios. Recargo brackets. The scout's calendar.
- 8
Case Files
Marcus, Sarah and Tom, David. Numbers preserved.
- 9
Glossary of the Modelo 721
15 terms, decoded.
- 10
Master Checklist — The 90-Day Countdown
Printable on one page.
- 11
The Spreadsheet Template
Formulas, worked example, evidence log.
Is it for you?
Built for
- Spanish tax residents holding >€50K on foreign crypto exchanges
- Crypto holders who missed a Modelo 721 deadline and need the correction protocol
- Professionals who want the 90-day countdown template ready before December
Not for
- Anyone seeking to hide foreign crypto from the AEAT
- Readers expecting legal advice
- Crypto holders with only Spanish custodians — the 721 doesn't apply
Written by Salah Nomad
Independent research with no commissions from any lawyer, agent or bank mentioned.