> ## Documentation Index
> Fetch the complete documentation index at: https://developers.uqpay.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Core concepts

> Understand card forms, funding modes, and configurable settings before issuing cards.

Before you start issuing cards, familiarize yourself with the key concepts that determine how a card behaves: its **form** (virtual or physical), its **mode** (Single or Share), and the **settings** you can configure at creation time.

## Card forms

Every card is either **virtual** or **physical**. You choose the form when you create or assign the card — it cannot be changed afterward.

### Virtual cards

A virtual card has no physical representation. It includes a PAN, expiration date, and CVV for digital transactions and is available immediately after creation.

* Created through the [Create Card](/card-issuance/v1.6/api-reference/create-card) endpoint.
* No activation required — the card is ready to use as soon as the `card.create.succeeded` webhook fires.
* Does not support ATM withdrawal.

### Physical cards

A physical card is a pre-manufactured card that must be assigned to a cardholder and activated before use.

* Assigned through the [Assign Card](/card-issuance/v1.6/api-reference/assign-card) endpoint.
* Requires [activation](/card-issuance/v1.6/guide/issue-physical-cards) before first use.
* Supports ATM withdrawal (for eligible BINs).

### Comparison

| Feature             | Virtual card                                                 | Physical card                                                |
| ------------------- | ------------------------------------------------------------ | ------------------------------------------------------------ |
| How to issue        | [Create Card](/card-issuance/v1.6/api-reference/create-card) | [Assign Card](/card-issuance/v1.6/api-reference/assign-card) |
| Activation required | No                                                           | Yes                                                          |
| ATM withdrawal      | Not supported                                                | Supported                                                    |
| Time to first use   | Immediate                                                    | After activation                                             |

## Card modes

Every card operates in one of two funding modes: **Single** or **Share**. The mode determines how funds flow between your issuing balance and the card.

### Single mode

Single mode works like a prepaid card. Funds are transferred from your issuing balance into the card at creation time.

* The issuing balance must be greater than or equal to the `card_limit` at creation time, or the request fails.
* Supports [recharge](/card-issuance/v1.6/api-reference/card-recharge) (add funds) and [withdraw](/card-issuance/v1.6/api-reference/card-withdraw) (remove funds).
* Does **not** support changing the card limit after creation.
* When the card is cancelled, the remaining balance is returned to the issuing balance automatically.

### Share mode

Share mode works like a debit card. The card draws directly from your issuing balance, with spending deducted in real time.

* No prior deposit is required — the card can be created even if the issuing balance is less than the `card_limit`.
* The `card_limit` acts as a spending cap, not a pre-funded amount.
* Supports changing the card limit after creation.
* Supports [recharge](/card-issuance/v1.6/api-reference/card-recharge) (increases `card_available_balance` without transferring funds) and [withdraw](/card-issuance/v1.6/api-reference/card-withdraw).
* No refund is needed on cancellation since no funds were transferred into the card.

### Comparison

| Feature                         | Single mode                                                                            | Share mode                                                    |
| ------------------------------- | -------------------------------------------------------------------------------------- | ------------------------------------------------------------- |
| Funding mechanism               | Pre-funded from issuing balance                                                        | Draws from issuing balance in real time                       |
| Balance requirement at creation | Issuing balance ≥ `card_limit`                                                         | No requirement                                                |
| Card limit changes              | Not supported                                                                          | Supported                                                     |
| Recharge                        | Transfers funds from issuing balance into the card; increases `card_available_balance` | Increases `card_available_balance` without transferring funds |
| Withdraw                        | Returns funds from the card to issuing balance; decreases `card_available_balance`     | Decreases `card_available_balance` without returning funds    |
| Cancellation refund             | Remaining balance returned automatically                                               | No refund needed                                              |

## Card settings

You configure these settings when creating or assigning a card:

| Setting                 | Description                                | Changeable after creation                                                          |
| ----------------------- | ------------------------------------------ | ---------------------------------------------------------------------------------- |
| **Card form**           | `VIRTUAL` or `PHYSICAL`                    | No                                                                                 |
| **Card mode**           | `SINGLE` or `SHARE`                        | No                                                                                 |
| **Settlement currency** | `USD` or `SGD`                             | No                                                                                 |
| **Card limit**          | Maximum spending amount for the card       | Share mode only                                                                    |
| **Spending controls**   | Per-transaction spending limits            | Yes — see [Spending controls](/card-issuance/v1.6/guide/spending-controls)         |
| **MCC controls**        | Allowed or blocked merchant category codes | Yes — see [MCC controls](/card-issuance/v1.6/guide/spending-controls#mcc-controls) |

## Next steps

* [Quickstart](/card-issuance/v1.6/guide/quickstart) — Issue your first virtual card
* [Create cardholders](/card-issuance/v1.6/guide/create-and-manage-cardholders) — Register cardholder identities before issuing cards