Coinepay | How to Pay for LangSmith with a Coinepay Virtual Card

If you are looking to pay for LangChain services, the self-service card checkout covered here is for LangSmith. You can start with a free Developer account, add a card for pay-as-you-go trace usage, or upgrade to Plus. This guide explains what to check before entering a Coinepay virtual card and what to do if payment does not go through.

Choose the right LangSmith billing option

LangChain lists Developer, Plus and Enterprise as its public LangSmith plans. At the time of writing (October 2026), Developer is US$0 per seat per month for one seat and includes 5,000 base traces per month. Eligible usage beyond that allowance is pay-as-you-go once you enable card billing. Plus is US$39 per seat per month, includes 10,000 base traces per month, and charges for additional usage on a pay-as-you-go basis. Check LangChain’s official pricing page before committing, as pricing and included usage can change.

Enterprise has custom pricing through sales and, according to LangChain’s pricing page, is invoiced annually upfront. It does not use the Plus self-service upgrade flow. LangSmith for Startups is a separate application program with Build and Scale tiers; follow the offer shown to your organization rather than assuming a standard Plus checkout applies.

LangChain says LangSmith plans are paid in USD across its supported cloud regions. Developer and Plus seats are billed on the first of the month, with seats added mid-month prorated. Removed seats do not receive a credit, while trace usage is billed monthly in arrears. Review both your seat count and likely trace usage before adding a payment method.

What you need before checkout

A LangSmith account: You can create a free account using Google, GitHub or email. Choose your intended cloud region during account creation. Supported instances include GCP US, GCP EU, GCP APAC and AWS US; a LangSmith organization cannot later migrate between regions or share billing with organizations in other regions. These are hosting locations, not a list of countries where card payments are accepted.
A verified Coinepay account: Register and complete identity verification before using card services. Your virtual card’s number, expiry date and CVV are available after issuance in the Coinepay app or self-service dashboard.
Enough available funds: Allow for the charge LangSmith presents, any subsequent usage charges, and applicable tax. Check your available balance and relevant card settings in Coinepay before proceeding.
Accurate billing information: Use your real name or business information and your genuine billing address. Have an invoice email and applicable tax ID ready if you plan to upgrade to Plus.

LangSmith describes its self-service payment entry as a credit-card flow. That description is not confirmation that every virtual card qualifies. Contact Coinepay support to confirm your card meets LangSmith’s stated payment requirement before you buy; you may also need to ask LangChain about its checkout rules. Do not assume a particular card will be accepted.

Set up LangSmith and pay with your Coinepay card

Create your Coinepay card. If you have not registered, create a Coinepay account and complete identity verification. Use the Coinepay app or dashboard to obtain your virtual card number, expiry date and CVV. Confirm the available balance and review any settings relevant to the intended payment.
Create or open your LangSmith account. In the LangSmith UI, sign up with Google, GitHub or email. Select the region where you want your organization hosted when prompted. If you already belong to an organization, check that you are working in the organization you intend to pay for.
Pick the appropriate billing path. To enable charges for Developer usage beyond the included 5,000 base traces, go to Settings → Billing and Usage and select Add card. To purchase the self-service Plus plan, choose Upgrade to Plus.
Enter your payment and billing details. Supply the Coinepay virtual card details in LangSmith’s card form. For Plus, also provide the requested business information, invoice email and applicable tax ID. Enter your genuine billing address exactly as it should appear for payment and invoicing; do not substitute a different country or address to try to pass a check.
Review and confirm. Check the plan, seat count, billing information and any amount displayed by LangSmith before submitting. Complete any authentication prompt that legitimately appears. Then return to the organization’s billing area to verify the resulting plan or payment status rather than submitting the form repeatedly.

If your organization needs Enterprise, contact LangChain sales for its agreement and invoice process. A Coinepay card entry in the Developer or Plus checkout is not a substitute for an Enterprise invoicing arrangement.

If your card is declined or checkout does not finish

A failed attempt does not, by itself, identify the cause. LangChain’s reviewed billing guidance does not provide a definitive list of checkout error messages or decline codes, so use the message you actually see and any information available from your card provider. The checks below are possibilities, not diagnoses.

Insufficient available balance

Compare your Coinepay available balance with the amount presented at checkout, including any displayed tax. Remember that Plus seats and trace usage have different billing timing: a successful initial purchase does not mean later usage charges will fit the remaining balance. Check the card and funding details in your Coinepay app or dashboard before retrying. If the displayed amount is unexpected, review the LangSmith plan and seat count first.

Billing address or identity mismatch

Recheck the card number, expiry date, CVV, name and billing fields for typing errors. Use your real billing details and ensure the information entered for the LangSmith organization is accurate. If the address associated with your card needs updating, check Coinepay’s available settings or contact support; do not enter an invented address or another person’s details.

3-D Secure or another authentication step

If checkout presents a bank or card authentication challenge, follow the instructions shown and make sure you can access the legitimate channel used for that challenge. If it expires or fails, check the payment status before trying again. Authentication behavior can vary, so do not assume your card will receive a particular type of prompt. Ask Coinepay support for help with a card-side authentication issue and LangChain support for a checkout-side issue.

Merchant payment or region checks

LangSmith’s credit-card checkout may apply payment-method or location checks. Its GCP and AWS cloud-region choices describe where organizations are hosted; they do not establish whether a particular card or billing country will be accepted. Check that you selected the intended organization and region and supplied truthful billing details. If the merchant rejects the payment method or region, ask LangChain what its requirements are and contact Coinepay support to confirm whether your card meets them. Do not use a false address or other workaround to bypass a restriction.

If you need help, keep the exact error text, the time of the attempt and the organization involved. Share those details with the relevant support team, but do not send your full card number or CVV in an ordinary support message.

Manage the card, subscription and invoices

To change the card on an existing LangSmith organization, open Settings → Plans & Billing → Billing → Update. Check the organization and billing details before saving the replacement. You can manage your Coinepay card from its dashboard or mobile app, available for iOS and Android.

For a Plus or Startup subscription, LangChain’s cancellation path is Settings → Usage and Billing → Plans and Billing → Cancel Subscription. Access remains active through the current billing period, and cancellation does not automatically turn the organization into a free one. Review the organization’s status and any continuing usage before assuming further charges have stopped.

LangChain’s terms generally make paid fees non-refundable, subject to exceptions in the applicable agreement. If an invoice contains incorrect billing details, update those details and contact LangChain support promptly: its published invoice-correction procedure concerns the most recent billing cycle’s invoice, not a general right to a refund. Keeping your business information and invoice email accurate at checkout is the simplest way to avoid that issue.

Get your Coinepay virtual card: Sign up · App Store · Google Play · Customer support

FAQ

Can I use a Coinepay virtual card for LangSmith Plus?

LangSmith offers a self-service Plus credit-card checkout, but acceptance of a particular virtual card is not guaranteed. Contact Coinepay support to confirm your card meets the stated requirement before buying.

Do I need a paid plan to start using LangSmith?

No. The Developer plan includes one seat and 5,000 base traces per month. You can add a card under Settings → Billing and Usage to enable eligible pay-as-you-go usage beyond that allowance.

Where can I update my LangSmith payment card?

In the relevant LangSmith organization, go to Settings → Plans & Billing → Billing → Update.

What should I do if LangSmith declines my card?

Check the available balance, card details and real billing address; complete any authentication prompt; then ask LangChain about merchant requirements and Coinepay support about card-side issues. Save the exact error text.

How to Pay for LangSmith with a Coinepay Virtual Card