This document explains how payments actually work in Mexico, what to prioritize in checkout design, and how to operate settlements, refunds, and risk without surprises.
1. The Reality of Payments in Mexico (Context First)
Mexico is not card-only and not instant-refund-friendly.
A strong Mexican checkout is built around:
Bank transfers (SPEI) as a primary rail
Cash-based methods for unbanked or privacy-driven users
Cards with intelligent 3DS orchestration
If cards are your conversion engine, SPEI is your volume engine.
2. The Bread & Butter of a Mexico Checkout
What Really Converts in Mexico
1️⃣ SPEI (Bank Transfers)
This is the most important rail for:
High-value deposits
VIPs
Gambling / Forex users
Repeat players
2️⃣ Cards (Credit & Debit)
Strong for first-time users (FTDs)
Needs smart 3DS, not blanket enforcement
3️⃣ OXXO / Cash
Critical for:
Unbanked users
Users without cards
Privacy-first players
Slower, but very sticky
4️⃣ Mercado Pago
Familiar brand
Trust-driven conversions
Separate ecosystem
Ideal Checkout Priority (Recommended)
SPEI (Frictionless first)
Cards
OXXO Pay
Cash Vouchers
Mercado Pago
This order maximizes:
Conversion
Ticket size
Operational simplicity
3. Card Payments – Detailed Flow
Card Deposit Flow (End to End)
1. User enters amount & card details
2. Pre-checks
BIN analysis
Velocity checks
Device & behavioral signals
Guardian pre-risk evaluation
3. 3DS Decisioning
Low-risk → frictionless
Medium-risk → 3DS challenge
High-risk → decline or step-up
4. Issuer Authorization
Approved → success
Declined → declined status
Timeout / error → failed
5. User Credited
Immediate on success
Operational Characteristics
Min: $10 MXN
Max: Bank-dependent
Recommended cap (Gambling / Forex): $200,000 MXN
Confirmation: Real-time
Refund Flow (Cards)
1. Merchant triggers refund (full or partial)
2. Refund sent to issuer
3. Issuer credits user (1–45 business days)
⚠️ Important:
Refund timing is out of your control
Chargebacks still apply
Card Risk & Compliance
PCI-DSS compliant
3DS 2.0 (rules + whitelists)
Velocity & behavior-based monitoring
Guardian AI pre-check
PayOps monitoring & manual intervention
4. SPEI – Standard vs Frictionless (Critical Section)
What SPEI Is
SPEI is Mexico’s real-time interbank transfer system.
Funds move bank-to-bank, not card-to-bank.
Once credited, money is final.
4.1 Standard SPEI Flow (Legacy)
1. User creates checkout
Amount generated
Reference assigned
2. User transfers via bank app
Must match:
Amount
Reference
Timing
3. SPEI confirmation received
If perfect → auto-credit
If mismatch → manual review
❌ This creates:
Tickets
Delays
Ops workload
4.2 Frictionless SPEI Flow (Modern / Recommended)
What Changes
No voucher. No checkout dependency.
Each user receives a unique CLABE.
Frictionless SPEI Flow
1. User sees their personal CLABE
2. User transfers from any bank
Any amount
Any timing
3. System receives SPEI payment
4. Smart matching engine evaluates
Sender account
Amount patterns
Historical behavior
Device & user linkage
5. Auto-credit decision
High confidence → credited instantly
Edge case → flagged for Ops
6. User balance updated
Why This Is a Game-Changer
✅ Massive reduction in support tickets
✅ Higher conversion (especially VIPs)
✅ No “sent wrong amount” issues
✅ Near-zero reconciliation pain
This is the bread & butter rail for serious Mexico volume.
SPEI Operational Characteristics
Min: $1 MXN
Max: No hard cap
Recommended cap (Gambling / Forex): $200,000 MXN
Speed: Seconds to minutes
Finality: Irreversible once credited
SPEI Refund Reality (Important)
❌ No automatic refunds
❌ No reversals
Refunds require:
Manual Ops approval
Outbound bank transfer
Settlement balance availability
👉 Operators must align refund policies accordingly.
5. OXXO Pay – Flow & Behavior
OXXO Pay Flow
1. User selects OXXO Pay
2. Voucher generated
Reference code
Expiration time
3. User pays in cash at OXXO store
4. Retailer confirms payment
5. User credited
⏱ Confirmation delay:
Minutes to hours
Sometimes same-day, sometimes next-day
OXXO Characteristics
Min: $10 MXN
Max: $10,000 MXN
Refunds: ❌ Not supported
Refunds handled as:
Manual reimbursements
Internal balance credits
Risk Profile
Very low fraud
No chargebacks
Delayed confirmation must be managed in UX
6. Cash Vouchers (Retail Cash)
Cash Voucher Flow
1. Voucher generated
2. User pays at participating retailer
3. Retailer confirms
4. User credited
Characteristics
Limits: ~$5,000 – $20,000 MXN (chain-dependent)
Refunds: ❌ Not supported
Risk: Extremely low
7. Mercado Pago – Separate Ecosystem
Flow
1. User redirected to Mercado Pago
2. Payment authorized inside MP
3. Confirmation returned
4. User credited
Key Difference
⚠️ Funds do NOT settle through Tonder
Merchant receives funds directly
Tonder:
Processes
Reports
Reconciles
Refunds are fully handled by Mercado Pago.
8. Settlement Flows (All Methods)
Default Settlement Model
Bi-weekly
Tuesday
Friday
Settlement Flow
1. Transactions processed
2. Only successful & cleared included
3. Deductions applied
Fees
IVA
Rolling reserves (if applicable)
4. Net payout executed
Optional Models
T+1 (Speed) – Faster liquidity
T+2 (Flow) – Better cash & risk balance
9. What Operators Must Be Operationally Ready For
Ops Team
SPEI manual refunds
Delayed OXXO confirmations
Edge-case SPEI reviews (rare with frictionless)
Finance Team
Reserve tracking
Settlement reconciliation
Mercado Pago off-platform settlements
Risk Team
3DS tuning (not blanket enforcement)
SPEI velocity thresholds
Bonus abuse & behavior monitoring
10. Final Operator Takeaway
If you remember only three things:
1️⃣ SPEI and cards are the backbone of Mexico payments
2️⃣ Frictionless SPEI is the biggest operational unlock
3️⃣ Refund logic must adapt per method — not all money is reversible
When done right, Mexico becomes:
High volume
Low chargeback
Operationally scalable

