diff --git a/esphome/components/sha256/sha256.cpp b/esphome/components/sha256/sha256.cpp
index a3e06cae2f..b1a949b504 100644
--- a/esphome/components/sha256/sha256.cpp
+++ b/esphome/components/sha256/sha256.cpp
@@ -34,6 +34,35 @@ void SHA256::calculate() {
   mbedtls_sha256_finish(&this->ctx_->ctx, this->ctx_->hash);
 }
 
+#elif defined(USE_ESP8266)
+
+SHA256::~SHA256() = default;
+
+void SHA256::init() {
+  if (!this->ctx_) {
+    this->ctx_ = std::make_unique<SHA256Context>();
+  }
+  br_sha256_init(&this->ctx_->ctx);
+  this->ctx_->calculated = false;
+}
+
+void SHA256::add(const uint8_t *data, size_t len) {
+  if (!this->ctx_) {
+    this->init();
+  }
+  br_sha256_update(&this->ctx_->ctx, data, len);
+}
+
+void SHA256::calculate() {
+  if (!this->ctx_) {
+    this->init();
+  }
+  if (!this->ctx_->calculated) {
+    br_sha256_out(&this->ctx_->ctx, this->ctx_->hash);
+    this->ctx_->calculated = true;
+  }
+}
+
 #elif defined(USE_ARDUINO)
 
 SHA256::~SHA256() = default;
diff --git a/esphome/components/sha256/sha256.h b/esphome/components/sha256/sha256.h
index 5917f68572..b047cb66e7 100644
--- a/esphome/components/sha256/sha256.h
+++ b/esphome/components/sha256/sha256.h
@@ -7,6 +7,8 @@
 
 #ifdef USE_ESP32
 #include "mbedtls/sha256.h"
+#elif defined(USE_ESP8266)
+#include <bearssl/bearssl_hash.h>
 #elif defined(USE_ARDUINO)
 #include <SHA256.h>
 #endif
@@ -38,6 +40,12 @@ class SHA256 {
     mbedtls_sha256_context ctx;
     uint8_t hash[32];
   };
+#elif defined(USE_ESP8266)
+  struct SHA256Context {
+    br_sha256_context ctx;
+    uint8_t hash[32];
+    bool calculated{false};
+  };
 #elif defined(USE_ARDUINO)
   struct SHA256Context {
     ::SHA256 sha;