Can I get a refund if I cancel the postal deduction in 30 yuan?

I can't. Postal deduction is generally the cost of short message service in 30 yuan. If you have agreed to handle this business and have been detained in 30 yuan, but later do not want to use this business, you can call the customer service hotline of Postal Savings Bank to cancel this business. However, after the business is cancelled, the deducted fees are usually not refunded.