diff --git a/esphome/components/i2c/i2c.h b/esphome/components/i2c/i2c.h
index 48a6e751cf..aab98d5f46 100644
--- a/esphome/components/i2c/i2c.h
+++ b/esphome/components/i2c/i2c.h
@@ -267,37 +267,6 @@ class I2CDevice {
 
   bool write_byte_16(uint8_t a_register, uint16_t data) const { return write_bytes_16(a_register, &data, 1); }
 
-  // Deprecated functions
-
-  ESPDEPRECATED("The stop argument is no longer used. This will be removed from ESPHome 2026.3.0", "2025.9.0")
-  ErrorCode read_register(uint8_t a_register, uint8_t *data, size_t len, bool stop) {
-    return this->read_register(a_register, data, len);
-  }
-
-  ESPDEPRECATED("The stop argument is no longer used. This will be removed from ESPHome 2026.3.0", "2025.9.0")
-  ErrorCode read_register16(uint16_t a_register, uint8_t *data, size_t len, bool stop) {
-    return this->read_register16(a_register, data, len);
-  }
-
-  ESPDEPRECATED("The stop argument is no longer used; use write_read() for consecutive write and read. This will be "
-                "removed from ESPHome 2026.3.0",
-                "2025.9.0")
-  ErrorCode write(const uint8_t *data, size_t len, bool stop) const { return this->write(data, len); }
-
-  ESPDEPRECATED("The stop argument is no longer used; use write_read() for consecutive write and read. This will be "
-                "removed from ESPHome 2026.3.0",
-                "2025.9.0")
-  ErrorCode write_register(uint8_t a_register, const uint8_t *data, size_t len, bool stop) const {
-    return this->write_register(a_register, data, len);
-  }
-
-  ESPDEPRECATED("The stop argument is no longer used; use write_read() for consecutive write and read. This will be "
-                "removed from ESPHome 2026.3.0",
-                "2025.9.0")
-  ErrorCode write_register16(uint16_t a_register, const uint8_t *data, size_t len, bool stop) const {
-    return this->write_register16(a_register, data, len);
-  }
-
  protected:
   uint8_t address_{0x00};  ///< store the address of the device on the bus
   I2CBus *bus_{nullptr};   ///< pointer to I2CBus instance
diff --git a/esphome/components/i2c/i2c_bus.h b/esphome/components/i2c/i2c_bus.h
index 3de5d5ca7b..2bc0dc1ef9 100644
--- a/esphome/components/i2c/i2c_bus.h
+++ b/esphome/components/i2c/i2c_bus.h
@@ -1,8 +1,6 @@
 #pragma once
 #include <cstddef>
 #include <cstdint>
-#include <cstring>
-#include <memory>
 #include <utility>
 #include <vector>
 
@@ -24,18 +22,6 @@ enum ErrorCode {
   ERROR_CRC = 7,               ///< bytes received with a CRC error
 };
 
-/// @brief the ReadBuffer structure stores a pointer to a read buffer and its length
-struct ReadBuffer {
-  uint8_t *data;  ///< pointer to the read buffer
-  size_t len;     ///< length of the buffer
-};
-
-/// @brief the WriteBuffer structure stores a pointer to a write buffer and its length
-struct WriteBuffer {
-  const uint8_t *data;  ///< pointer to the write buffer
-  size_t len;           ///< length of the buffer
-};
-
 /// @brief This Class provides the methods to read and write bytes from an I2CBus.
 /// @note The I2CBus virtual class follows a *Factory design pattern* that provides all the interfaces methods required
 /// by clients while deferring the actual implementation of these methods to a subclasses. I2C-bus specification and
@@ -68,50 +54,6 @@ class I2CBus {
     return this->write_readv(address, buffer, len, nullptr, 0);
   }
 
-  ESPDEPRECATED("This method is deprecated and will be removed in ESPHome 2026.3.0. Use write_readv() instead.",
-                "2025.9.0")
-  ErrorCode readv(uint8_t address, ReadBuffer *read_buffers, size_t count) {
-    size_t total_len = 0;
-    for (size_t i = 0; i != count; i++) {
-      total_len += read_buffers[i].len;
-    }
-
-    SmallBufferWithHeapFallback<128> buffer_alloc(total_len);  // Most I2C reads are small
-    uint8_t *buffer = buffer_alloc.get();
-
-    auto err = this->write_readv(address, nullptr, 0, buffer, total_len);
-    if (err != ERROR_OK)
-      return err;
-    size_t pos = 0;
-    for (size_t i = 0; i != count; i++) {
-      if (read_buffers[i].len != 0) {
-        std::memcpy(read_buffers[i].data, buffer + pos, read_buffers[i].len);
-        pos += read_buffers[i].len;
-      }
-    }
-    return ERROR_OK;
-  }
-
-  ESPDEPRECATED("This method is deprecated and will be removed in ESPHome 2026.3.0. Use write_readv() instead.",
-                "2025.9.0")
-  ErrorCode writev(uint8_t address, const WriteBuffer *write_buffers, size_t count, bool stop = true) {
-    size_t total_len = 0;
-    for (size_t i = 0; i != count; i++) {
-      total_len += write_buffers[i].len;
-    }
-
-    SmallBufferWithHeapFallback<128> buffer_alloc(total_len);  // Most I2C writes are small
-    uint8_t *buffer = buffer_alloc.get();
-
-    size_t pos = 0;
-    for (size_t i = 0; i != count; i++) {
-      std::memcpy(buffer + pos, write_buffers[i].data, write_buffers[i].len);
-      pos += write_buffers[i].len;
-    }
-
-    return this->write_readv(address, buffer, total_len, nullptr, 0);
-  }
-
  protected:
   /// @brief Scans the I2C bus for devices. Devices presence is kept in an array of std::pair
   /// that contains the address and the corresponding bool presence flag.