Square Developer Terms of Service

Last updated: September 10, 2026

We’ve included annotations in the gray boxes below to emphasize certain portions of our notice and help guide you as you read them. Annotations aren’t part of the terms and have no legal effect, but they should help you follow the text.

These Square Developer Terms of Service (“Developer Terms”) are a legal agreement between you (“you,” “your”) and Block, Inc. (“Square,” “we,” “our” or “us”) governing your use of Square’s software development kit files (SDKs), tools, programs and utilities, as well as any plug-in or other application programming interfaces (“APIs”), sample code (including runtimes and libraries) and related documentation (collectively the “Developer Tools”). By using the Developer Tools, and related materials made available to you, you agree to be bound by these Developer Terms and any documentation and guidelines accompanying the Developer Tools, the General Terms of Service, the Privacy Notice, and all other terms, policies, and guidelines applicable to your use, including but not limited to, the Payment Terms if you accept payments through Square.

1. Your access to and use of Square Developer Tools and Content

Use our Developer tools and services only as in these terms and in our documentation. You are responsible for how you use our services. We can change or stop offering these services at any time.

1. You may use the Developer Tools to access information created or retained in a Square account (“Content”) and use Square payment processing services in connection with the applications, websites, products or services you operate and offer that interact with Developer Tools (“Your Service”). Any payment processing enabled by you via a Square API requires a Square account and is subject to the General Terms. You are solely responsible for, and Square disclaims all liability for, Your Service.

2. Your use of the Developer Tools and Content is subject to certain limitations on access, calls and use as set forth in these Developer Terms, in the Square documentation accompanying such Developer Tools, or as otherwise provided to you by Square. If Square assigns you developer credentials or client IDs, you must use them with applicable Developer Tools. You will not misrepresent or mask either your identity or Your Service’s identity when using the Developer Tools or developer accounts. If Square believes that you have attempted to exceed or circumvent these limitations, your ability to use the Developer Tools and Content may be temporarily or permanently blocked.

3. Square may update the Developer Tools at any time, and may discontinue support for previous versions of the Developer Tools at Square’s sole discretion. Square will make reasonable efforts to notify you when a version of the Developer Tools will no longer be supported.

4. If Your Service enables Square account holders (“Square Sellers”) to access their Content, Square Sellers must be presented with the ability to log into Square via the OAuth protocol. Sellers without a Square account should be given the opportunity to create a new Square account as provided by Square. You will not solicit or store Square passwords.

5. You will use the Developer Tools and operate Your Services which access the Developer Tools only as permitted by law (including without limitation, laws regarding the import or export of data or software, privacy, or data-security as applicable). You will not use the Developer Tools to encourage or promote illegal activity. You will only access the applicable Developer Tools following the implementation instructions and other requirements specified in the documentation for such Developer Tools, or as otherwise provided by Square from time to time.

6. You are fully responsible for the security of data on your site and processed via Your Services. You agree that at all times you and Your Services will, at your effort and expense, be compliant with the Payment Card Industry Data Security Standard (PCI DSS), the Payment Application Data Security Standard (PA-DSS), as applicable, and all applicable laws bearing on data privacy and cybersecurity. At Square’s request, you will promptly provide us with documentation evidencing your compliance with PCI DSS, PA-DSS, and/or applicable law. You will use and access the Developer Tools in accordance with the documentation and instructions provided by Square and in no circumstances will you store, process or transmit any cardholder’s account number, expiration date, or CVV2 except as described in that documentation. Further, you may not disclose card information to any third party, other than in connection with processing card transactions requested by your customer under Your Service and in a manner consistent with PCI DSS and applicable law.

7. You provide Square with a paid-up, royalty-free, revocable, worldwide, non-exclusive, non-transferable license to use Your Services for testing, review or other related purposes to ensure that Your Services comply with these Developer Terms. You may revoke this license at any time by providing written notice to us. If you revoke this license, your access to the Developer Tools and Content will immediately terminate.

8. If Your Service is provided at a fee to your customers, the fees you charge will be identified separately from the fees Square charges for its services.

9. If you are using the Developer Tools to access and use the Apple Pay Web APIs and Apple Pay Platform, you must first accept the [Apple Pay Platform Web Merchant Terms and Conditions][1].

10. If you are using the Developer Tools to access and use the Google Pay API, you must first accept the [Google Pay API Terms of Service][2].

11. You may use certain Square APIs to facilitate payment collection by Square from Square Sellers. Where available, Square APIs may be used to facilitate your collection of fees from Square Sellers. You are responsible for clearly and accurately describing the fees you collect from Square Sellers and obtaining all required consents in connection with those fees, and you will notify Square Sellers prior to making any changes to those fees. If you are utilizing Square APIs in order to charge fees to Square Sellers on a per-transaction basis, then you authorize Square to act as your agent for the limited purposes of holding, receiving, and disbursing payments, consisting of and/or sourced from such Square Sellers’ payment processing proceeds. You acknowledge and agree that Square does not act on your behalf or on the Square Sellers’ behalf as money transmitter or a money services business (as those terms are commonly construed under applicable law) or in any other similar capacity except as expressly provided in these Developer Terms. You acknowledge and agree that you will be solely responsible and liable for collecting and remitting to the applicable governmental taxing authority any sales, use, value-added or similar taxes that may be applicable to your sales of Your Service utilizing Square APIs (“your Indirect Taxes”), as well as resolving any disputes that may arise between you and any Square Seller who uses Your Services. Notwithstanding the foregoing, where Square is required by applicable law as marketplace facilitator/provider (when utilizing Square APIs to facilitate payment collection by Square from Square Sellers) to collect your Indirect Taxes and remit such taxes to a state or local tax authority, you acknowledge and agree that Square may calculate, collect, and withhold your Indirect Taxes on a per-transaction basis from your payment processing proceeds, in order to remit your Indirect Taxes to the applicable governmental taxing authority.

2. Developer Tools Access Prohibitions

Don’t resell or sublicense our developer tools or content, don’t create a service that does the same thing that we do, don’t create a service that allows for migration of sellers from Square, and don’t use Square Content or data to train or otherwise enhance any AI System.

You will not, nor will you permit another party to:

1. sell, rent, lease, sublicense, redistribute or syndicate access to the Developer Tools or to Content other than your own;
2. create a service that functions substantially the same as the Developer Tools or any Square service;
3. create a service that allows Square Sellers to migrate from Square to a third party service or platform, unless Square, at its sole discretion, does not otherwise prohibit or impose conditions on the creation of such service; or
4. use any Content or other data received from Square (anonymized or not) to train or otherwise enhance any “AI System” (as defined in Section 7).

3. Content Prohibitions

Don’t access or store a Square seller’s information unless that seller allows it. If allowed, don’t abuse your access, and be clear to the seller why and how you will be using their content. Delete and stop accessing content if the seller no longer wants your app to access their information.

You will not, nor will you permit another party, without the express consent of the Square Seller, to:

1. scrape, access, download, store, build databases or otherwise create permanent copies of any Square Seller’s Content, including Content related to or provided by any customer of any Square Seller;

2. copy, translate, modify, create derivative work of, sell, lease, sublicense, distribute or publicly display any of such Square Seller’s Content; or

3. make statements or represent yourself or Your Service as an agent of Square.

Additionally, you and Your Service will clearly identify its purpose to the Square Seller and not mislead or deceive Square Sellers with respect to the functionality Your Service performs on behalf of the Square Seller or to what Content Your Service may access, store, and manipulate.

If a Seller who uses your application revokes your permission to access their Content (“Revoking Seller”), you agree to: (a) immediately stop accessing the Revoking Seller Content, and (b) delete any and all Revoking Seller Content from your systems. You further agree that Square has the right to audit your deletion of the Revoking Seller Content at any time, including after your Square account has been terminated.

4. Submission of Content

We have broad license rights over content you submit or display through our service. We will only use your content to provide our services and as allowed under our privacy notice. You agree that you have the rights needed to license us content you submit through our services.

Certain Developer Tools allow for the submission of content, and except as expressly provided in these Developer Terms, Square does not acquire any ownership of any intellectual property rights that you or the Square Sellers hold in the content that you submit using the Developer Tools. By submitting, posting or displaying content to or from the Developer Tools through Your Service, you give Square a perpetual, irrevocable, worldwide, royalty-free, and non-exclusive license to reproduce, adapt, modify, translate, publish, publicly perform, publicly display and distribute such content. However, Square will only use such content for the purpose of enabling Square to provide its services, the Developer Tools and only in accordance with the Privacy Notice and other applicable policies. You represent that, before you submit content via the Developer Tools and Your Service, you have the necessary rights (including any necessary rights from Square Sellers) to grant us the license.

5. Use of Square Marks

We own the Square logos and trademarks that we make available through our services, and you may use them on our terms. We may change our marks at any time and you must use current versions.

We may also periodically make available certain Square logos, trademarks, or other identifiers for your use as set forth in Built with Square (“Square Marks”). If we do so, you will use them subject to and in accordance with Square’s then current Built with Square and Square for Developers Trademark Terms. Square may limit or revoke your ability to use Square Marks at any time. All rights not provided in the Square for Developers Trademark Terms are expressly reserved by Square. We may change Square Marks from time to time. In the event that Square Marks or Square for Developers Trademark Terms are changed, you will (a) use the current version of the Square Marks and (b) use Square Marks consistent with the then current Square Trademarks Terms.

6. Ownership. Feedback

We own all rights in our tools, marks, content and services. Square sellers retain rights to their content. You retain rights to your apps, websites, products or services that interact with our services.

We can freely use any feedback you give us at no charge.

You expressly acknowledge that Square or the Square Seller retains all worldwide right, title and interest in and to Content, including all intellectual property rights therein.

You also acknowledge that as between you and Square, Square owns all right, title and interest in and to the Developer Tools, Square Marks, and Square services (and any derivative works or enhancements thereof), including but not limited to all intellectual property rights therein. You agree not to do anything inconsistent with such ownership. Any rights not expressly granted herein are withheld.

Subject to Section 1 above and this Section 6, as between you and Square, you retain all worldwide right, title and interest in and to Your Service, including but not limited to all intellectual property rights therein.

You may provide Square with comments concerning Content or the Developer Tools or your evaluation and use thereof. You agree that Square and its designees will be free to copy, modify, create derivative works, publicly display, disclose, distribute, license and sublicense, incorporate, and otherwise use the feedback, including derivative works thereto, for any and all commercial and non-commercial purposes with no obligation of any kind to you.

7. AI Usage

If you use Square’s Developer Tools and incorporate AI in the provision of your services, you make certain reps and warranties to Square, as described below.

Without limiting any other provisions in these Developer Terms, including but not limited to any prohibitions contained in Section 2 above, you represent and warrant to Square that: (a) any AI System used by you complies with all laws and regulations; and (b) you have obtained sufficient rights, consents, and disclosures necessary to use any data used to train or otherwise enhance the AI System.

You acknowledge that the AI Systems can make mistakes or provide incorrect, inaccurate, or offensive outputs, including text, audio, images, content, data, or other output. It is your responsibility to always check the accuracy and appropriateness of the outputs.

You should not use any AI Systems or outputs in any way that is harmful, misleading, or violates the rights of any person or entity. In addition to Square’s other rights, Square reserves the right to suspend, terminate, or otherwise modify your access to Developer Tools as determined in our sole discretion if we identify any such misuse.

In addition to any limitations covered in other applicable terms, you agree that you will not access or use, or allow, encourage, facilitate, or instruct others to access or use, AI Systems or outputs in a manner that:

• Makes decisions impacting the terms or conditions of hiring or employment;
• Misleads anyone that the content generated by AI Products is human-generated;
• Generates or disseminates:
  1. Content that is misleading, illegal, fraudulent, deceptive, or could lead to harm; abusive, hateful, inflammatory, or could lead to harm (such as self-harm, discrimination, bullying, humiliation, or other emotional harms);
  2. Content that may violate or infringe upon the rights of others, including privacy or data protection rights, intellectual property rights, and other proprietary rights;
  3. Content that may be libelous, slanderous, or otherwise defamatory;
  4. Political content, including for dissemination in electoral campaigns;
  5. Spam, ransomware, keyloggers, viruses or other software;
  6. Content that contains corrupted data or any other harmful, disruptive, or destructive files;
  7. Hateful, harassing, abusive, violent, or highly offensive content that attacks or dehumanizes a group based on race, ethnicity, national origin, religion, serious disease or disability, gender, age, or sexual orientation;
  8. Contains adult content, pornographic material, images of explicit nudity, depictions of graphic violence or gore, or content that otherwise promotes, glorifies, or threatens violence;
  9. Content promoting or generating violent extremism or terrorist content;
  10. Content that encourages committing any type of crimes; or
  11. Content related to child exploitation or sexual abuse.
• Impersonates any person or entity or falsely states or otherwise misrepresents your affiliation with a person or entity;
• Violates any applicable laws or regulations or promotes, contributes to, or encourages illegal or unlawful activity or activity that gives rise to civil liability; or
• Overrides safety or privacy filters, controls, or mechanisms.

“AI System” means any machine-based system that can perform tasks with some level of independence, and that may learn or improve over time after it has been deployed. An AI System uses inputs to generate outputs that can influence the physical or virtual world. This includes systems that use machine learning, generative AI, and other forms of artificial intelligence, along with the data, models, and other components (like weights and training sets) they rely on.

8. Termination

We can terminate or refuse your access to the tools at any time, for any reason. We can also change or discontinue a certain tool or feature at any time. You can terminate these developer terms by deactivating your Square Account at any time.

We may terminate these Developer Terms, suspend or terminate your Square account at any time for any reason, including, but not limited to, where Your Service allows Square Sellers to migrate from Square to a third party service or platform. We may add or remove, suspend, stop, delete, discontinue or impose conditions on the Developer Tools or any feature or aspect of the Developer Tools. We will take reasonable steps to notify you of termination by email or at the next time you attempt to access your Square account or the Developer Tools. You may also terminate these Developer Terms by deactivating your Square account at any time.

If these Developer Terms or your Square account is terminated or suspended for any reason: (a) the license and any other rights granted under these Developer Terms and any other applicable terms will end, (b) we may (but have no obligation to) delete your information and account data stored on our servers, and (c) Square shall not be liable to you or any third party for compensation, reimbursement, or damages for any termination or suspension of your Developer Tools, or for deletion of your information or account data.

If your Square account is terminated or suspended, you agree to: (a) continue to be bound by these Developer Terms, (b) immediately stop using the Developer Tools; (c) immediately stop accessing all Square Seller Content; and (d) delete all Square Seller Content from your systems. You further agree that Square has the right to audit your deletion of all Square Seller Content, including after your Square account has been terminated.

9. No Warranties

While we do our best to bring great products and services to our customers, we provide them as-is, without warranties. We are not responsible for any goods and services that you might buy or sell using Square’s services.

DEVELOPER TOOLS ARE PROVIDED “AS IS” WITHOUT REPRESENTATION OR WARRANTY, WHETHER IT IS EXPRESS, IMPLIED, OR STATUTORY. WITHOUT LIMITING THE FOREGOING, SQUARE SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.

SQUARE DOES NOT WARRANT OR GUARANTEE THAT THE DEVELOPER TOOLS ARE ACCURATE, RELIABLE OR CORRECT; THAT THE DEVELOPER TOOLS WILL MEET YOUR REQUIREMENTS; THAT THE DEVELOPER TOOLS WILL BE AVAILABLE AT ANY PARTICULAR TIME OR LOCATION, UNINTERRUPTED, ERROR-FREE, WITHOUT DEFECT OR SECURE; THAT ANY DEFECTS OR ERRORS WILL BE CORRECTED; OR THAT THE DEVELOPER TOOLS ARE FREE OF VIRUSES OR OTHER HARMFUL COMPONENTS. ANY CONTENT OR DATA DOWNLOADED OR OTHERWISE OBTAINED THROUGH THE USE OF THE DEVELOPER TOOLS ARE DOWNLOADED AT YOUR OWN RISK AND YOU WILL BE SOLELY RESPONSIBLE FOR ANY DAMAGE TO YOUR PROPERTY OR LOSS OF DATA THAT RESULTS FROM SUCH DOWNLOAD.

Square does not warrant, endorse, guarantee, or assume responsibility for any product or services advertised or offered by a third party. Square does not have control of, or liability for, goods or services that are paid for using the Developer Tools.