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    <title>DEV Community: Chiko Cordero</title>
    <description>The latest articles on DEV Community by Chiko Cordero (@chiko_cordero_807b83f2a7a).</description>
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      <title>DEV Community: Chiko Cordero</title>
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    <item>
      <title>How to check if a USDT (TRC20) address is frozen by Tether</title>
      <dc:creator>Chiko Cordero</dc:creator>
      <pubDate>Sun, 08 Nov 2026 20:41:46 +0000</pubDate>
      <link>https://dev.to/chiko_cordero_807b83f2a7a/how-to-check-if-a-usdt-trc20-address-is-frozen-by-tether-54n2</link>
      <guid>https://dev.to/chiko_cordero_807b83f2a7a/how-to-check-if-a-usdt-trc20-address-is-frozen-by-tether-54n2</guid>
      <description>&lt;p&gt;If you receive USDT on TRON, there is one check worth doing before you release&lt;br&gt;
fiat or goods: &lt;strong&gt;is the sender's address on Tether's blacklist?&lt;/strong&gt;&lt;/p&gt;

&lt;p&gt;A blacklisted address still shows its USDT balance in every wallet and explorer.&lt;br&gt;
But any transfer &lt;em&gt;from&lt;/em&gt; it reverts on-chain. If you accept funds that came&lt;br&gt;
through a frozen address, or trade with someone whose wallet gets frozen&lt;br&gt;
mid-deal, you find out the hard way.&lt;/p&gt;

&lt;h2&gt;
  
  
  Where the blacklist lives
&lt;/h2&gt;

&lt;p&gt;The blacklist is not a separate database. It is state inside the USDT-TRC20&lt;br&gt;
contract itself (&lt;code&gt;TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t&lt;/code&gt;). The contract exposes a&lt;br&gt;
read-only method, &lt;code&gt;getBlackListStatus(address)&lt;/code&gt;, which returns &lt;code&gt;true&lt;/code&gt; for frozen&lt;br&gt;
addresses. Tether can also call &lt;code&gt;destroyBlackFunds&lt;/code&gt; on a blacklisted address,&lt;br&gt;
which burns its balance.&lt;/p&gt;

&lt;p&gt;Because the state lives in the token contract, the answer is &lt;strong&gt;chain-specific&lt;/strong&gt;:&lt;br&gt;
a TRON result tells you nothing about the same owner's Ethereum or TON wallets.&lt;/p&gt;

&lt;p&gt;Fun fact to test your code with: the USDT contract address itself returns&lt;br&gt;
&lt;code&gt;true&lt;/code&gt;. Tether blacklisted its own contract, presumably so nobody can send&lt;br&gt;
tokens to it by mistake.&lt;/p&gt;

&lt;h2&gt;
  
  
  Reading it with TronWeb
&lt;/h2&gt;



&lt;div class="highlight js-code-highlight"&gt;
&lt;pre class="highlight javascript"&gt;&lt;code&gt;&lt;span class="k"&gt;import&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt; &lt;span class="nx"&gt;TronWeb&lt;/span&gt; &lt;span class="p"&gt;}&lt;/span&gt; &lt;span class="k"&gt;from&lt;/span&gt; &lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="s2"&gt;tronweb&lt;/span&gt;&lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="p"&gt;;&lt;/span&gt;

&lt;span class="kd"&gt;const&lt;/span&gt; &lt;span class="nx"&gt;USDT_TRC20&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="s2"&gt;TR7NHqjeKQxGTCi8q8ZY4pL8otSzgjLj6t&lt;/span&gt;&lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="p"&gt;;&lt;/span&gt;
&lt;span class="kd"&gt;const&lt;/span&gt; &lt;span class="nx"&gt;tronWeb&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="k"&gt;new&lt;/span&gt; &lt;span class="nc"&gt;TronWeb&lt;/span&gt;&lt;span class="p"&gt;({&lt;/span&gt; &lt;span class="na"&gt;fullHost&lt;/span&gt;&lt;span class="p"&gt;:&lt;/span&gt; &lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="s2"&gt;https://api.trongrid.io&lt;/span&gt;&lt;span class="dl"&gt;"&lt;/span&gt; &lt;span class="p"&gt;});&lt;/span&gt;

&lt;span class="k"&gt;export&lt;/span&gt; &lt;span class="k"&gt;async&lt;/span&gt; &lt;span class="kd"&gt;function&lt;/span&gt; &lt;span class="nf"&gt;isFrozen&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="nx"&gt;address&lt;/span&gt;&lt;span class="p"&gt;)&lt;/span&gt; &lt;span class="p"&gt;{&lt;/span&gt;
  &lt;span class="k"&gt;if &lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="o"&gt;!&lt;/span&gt;&lt;span class="nx"&gt;tronWeb&lt;/span&gt;&lt;span class="p"&gt;.&lt;/span&gt;&lt;span class="nf"&gt;isAddress&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="nx"&gt;address&lt;/span&gt;&lt;span class="p"&gt;))&lt;/span&gt; &lt;span class="k"&gt;throw&lt;/span&gt; &lt;span class="k"&gt;new&lt;/span&gt; &lt;span class="nc"&gt;Error&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="s2"&gt;Invalid TRON address&lt;/span&gt;&lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="p"&gt;);&lt;/span&gt;
  &lt;span class="nx"&gt;tronWeb&lt;/span&gt;&lt;span class="p"&gt;.&lt;/span&gt;&lt;span class="nf"&gt;setAddress&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="nx"&gt;address&lt;/span&gt;&lt;span class="p"&gt;);&lt;/span&gt; &lt;span class="c1"&gt;// constant calls need an owner address&lt;/span&gt;
  &lt;span class="kd"&gt;const&lt;/span&gt; &lt;span class="nx"&gt;usdt&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="k"&gt;await&lt;/span&gt; &lt;span class="nx"&gt;tronWeb&lt;/span&gt;&lt;span class="p"&gt;.&lt;/span&gt;&lt;span class="nf"&gt;contract&lt;/span&gt;&lt;span class="p"&gt;().&lt;/span&gt;&lt;span class="nf"&gt;at&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="nx"&gt;USDT_TRC20&lt;/span&gt;&lt;span class="p"&gt;);&lt;/span&gt;
  &lt;span class="kd"&gt;const&lt;/span&gt; &lt;span class="nx"&gt;result&lt;/span&gt; &lt;span class="o"&gt;=&lt;/span&gt; &lt;span class="k"&gt;await&lt;/span&gt; &lt;span class="nx"&gt;usdt&lt;/span&gt;&lt;span class="p"&gt;.&lt;/span&gt;&lt;span class="nf"&gt;getBlackListStatus&lt;/span&gt;&lt;span class="p"&gt;(&lt;/span&gt;&lt;span class="nx"&gt;address&lt;/span&gt;&lt;span class="p"&gt;).&lt;/span&gt;&lt;span class="nf"&gt;call&lt;/span&gt;&lt;span class="p"&gt;();&lt;/span&gt;
  &lt;span class="k"&gt;return&lt;/span&gt; &lt;span class="nx"&gt;result&lt;/span&gt; &lt;span class="o"&gt;===&lt;/span&gt; &lt;span class="kc"&gt;true&lt;/span&gt; &lt;span class="o"&gt;||&lt;/span&gt; &lt;span class="nx"&gt;result&lt;/span&gt;&lt;span class="p"&gt;?.&lt;/span&gt;&lt;span class="nf"&gt;toString&lt;/span&gt;&lt;span class="p"&gt;()&lt;/span&gt; &lt;span class="o"&gt;===&lt;/span&gt; &lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="s2"&gt;1&lt;/span&gt;&lt;span class="dl"&gt;"&lt;/span&gt;&lt;span class="p"&gt;;&lt;/span&gt;
&lt;span class="p"&gt;}&lt;/span&gt;
&lt;/code&gt;&lt;/pre&gt;

&lt;/div&gt;



&lt;p&gt;A few production notes:&lt;/p&gt;

&lt;ul&gt;
&lt;li&gt;
&lt;strong&gt;Validate first.&lt;/strong&gt; TRON addresses are Base58Check; reject anything that fails
&lt;code&gt;isAddress&lt;/code&gt; before you call the network.&lt;/li&gt;
&lt;li&gt;
&lt;strong&gt;Use timeouts.&lt;/strong&gt; Public TronGrid endpoints can be slow or rate-limited. Fail
"unknown", not "clean".&lt;/li&gt;
&lt;li&gt;
&lt;strong&gt;Cross-check.&lt;/strong&gt; TronScan also indexes blacklist events. If the contract read
and the index disagree, surface the disagreement instead of picking one.&lt;/li&gt;
&lt;li&gt;
&lt;strong&gt;A clean result is a point-in-time fact.&lt;/strong&gt; Addresses can be added after your
check, so store the timestamp with the answer.&lt;/li&gt;
&lt;/ul&gt;

&lt;h2&gt;
  
  
  Blacklist ≠ OFAC ≠ "risky"
&lt;/h2&gt;

&lt;p&gt;Three different questions often get mixed up:&lt;/p&gt;

&lt;ol&gt;
&lt;li&gt;
&lt;strong&gt;Tether blacklist&lt;/strong&gt;: an issuer control inside the token contract (above).&lt;/li&gt;
&lt;li&gt;
&lt;strong&gt;OFAC SDN&lt;/strong&gt;: a US Treasury sanctions list that includes some TRON addresses.
An address can be on one list and not the other.&lt;/li&gt;
&lt;li&gt;
&lt;strong&gt;AML risk indicators&lt;/strong&gt;: interpretation of exposure and flows. Useful
context, but a model's opinion, not a fact.&lt;/li&gt;
&lt;/ol&gt;

&lt;p&gt;Report them separately. Averaging them into one score hides the facts that&lt;br&gt;
actually matter.&lt;/p&gt;

&lt;h2&gt;
  
  
  If you don't want to build it
&lt;/h2&gt;

&lt;p&gt;I built &lt;a href="https://usdt.chikocorp.com/tron-usdt-blacklist-checker" rel="noopener noreferrer"&gt;TRON Checker&lt;/a&gt;&lt;br&gt;
to do exactly this: contract read plus TronScan cross-check, exact OFAC match,&lt;br&gt;
and explainable risk indicators. It's free for single checks, with no signup or&lt;br&gt;
wallet connection. There is also an &lt;a href="https://usdt.chikocorp.com/api-docs" rel="noopener noreferrer"&gt;API&lt;/a&gt;&lt;br&gt;
if you need it in a payment flow, and an&lt;br&gt;
&lt;a href="https://github.com/chico10117/tron-usdt-mcp" rel="noopener noreferrer"&gt;MCP server&lt;/a&gt; so AI agents can run&lt;br&gt;
the same check (paid tiers accept x402).&lt;/p&gt;

</description>
      <category>blockchain</category>
      <category>crypto</category>
      <category>cryptocurrency</category>
      <category>security</category>
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