---
title: Minimum top-up
description: Set the smallest and largest wallet top-up per payment, and understand the other balance floors that decide whether a customer can order.
url: https://nexcmp.com/docs/billing/minimum-top-up/
applies_to: NexCMP 1.6.1
updated: 2026-11-02
---

# Minimum top-up

> **Where in the admin:** Finance › Payment channels › Fees & limits (`/payments/fees`), card **Wallet & top-up (Billing › Policy)**.

## What it does

Every payment channel rejects an amount below the **minimum top-up** or above the **maximum top-up per transaction**. The defaults are **$10.00** and **$5,000.00**. Use the minimum to avoid tiny payments that cost more in gateway fees than they are worth.

## Requirements

| Item | Requirement |
|---|---|
| Role | An administrator. |
| Dependencies | None. |

## Set the limits

1. Open **Finance › Payment channels › Fees & limits** (`/payments/fees`).
2. In the card **Wallet & top-up (Billing › Policy)** edit **Min top-up (USD)** and **Max top-up per transaction (USD)**.
3. Click **Save Wallet & top-up**.

![Wallet and top-up card with the minimum top-up 10.00 and the maximum 5000.00](https://nexcmp.com/docs/images/billing/minimum-top-up-01-limits.webp)

| Setting | Default | Allowed range | Rule |
|---|---|---|---|
| Min top-up (USD) | $10.00 | $0 to $10,000 | Must be less than or equal to the maximum. |
| Max top-up per transaction (USD) | $5,000.00 | $1 to $1,000,000 | Must be at least the minimum. |

The values are stored in cents (`min_topup_cents`, `max_topup_cents`).

## Where the limits apply

| Place | Behaviour |
|---|---|
| Card, Apple/Google Pay, Link, Alipay, PayPal, USDT | Amounts outside the range are refused by the server. The portal shows "Enter an amount between {min} and {max}". |
| VN bank transfer | The VND amount must be inside the Sepay limits **and** its USD value (what the wallet receives) inside the minimum and maximum. The portal shows the larger of the two VND minimums. See [Bank transfer (Vietnam)](https://nexcmp.com/docs/billing/bank-transfer-vn/). |
| [Automatic top-up](https://nexcmp.com/docs/billing/auto-top-up/) | Every automatic charge is at least the minimum and at most the maximum. In fixed mode the customer's amount must be between the minimum and $1,000. |
| Top-up codes ([Vouchers](https://nexcmp.com/docs/billing/promotions/)) | Not affected. |
| Admin credit / debit | Not affected. |
| Reseller wallet top-up | A separate minimum (`rs_topup_min_cents`, default $20) under Resellers › Defaults. |

## Related floors

The minimum top-up is not the only balance rule. These are in **Services › Virtual Machines › Policy** (`/vm/policy`):

| Rule | Default | Meaning |
|---|---|---|
| Minimum balance (`min_balance_cents`) | $5.00 | The least wallet balance a customer needs to create a VM. |
| Quotas | Off | When **Quotas** are on, creating a VM also needs a balance covering a number of hours of that VM. See [Quotas](https://nexcmp.com/docs/billing/quotas/). |

## Verify

1. In the portal open **Billing › Deposit** and type an amount just under your minimum. The pay button is disabled and the range message appears.
2. Enter the minimum and confirm the payment starts.

## Limits & notes

- A change applies to new payments. Orders already created keep the amounts they were created with.
- The customer-facing hint ("Minimum $10.00, maximum $5,000.00") and the quick-amount buttons follow the new limits automatically.
- If you display VND (the **Exchange rates** page), the minimum is converted at the stored rate for display only; the wallet and the limits stay in USD.

## Troubleshooting

| Symptom | Cause | Fix |
|---|---|---|
| "Minimum top-up must be less than or equal to the maximum" | Values crossed | Lower the minimum or raise the maximum. |
| Customer cannot pay a small amount through VN bank transfer | Sepay VND minimum or the USD minimum is higher | Lower **Min / order** on the bank page or the USD minimum. |
| Server error `invalid_argument` on a top-up | Amount outside the range | Ask for an amount inside the displayed range. |