Question: When called to the Torah for an aliyah, may one recite the berachot silently?
Answer: Contrary to the custom of many, it is not halachically proper to say the berachot silently.
The Shulchan Aruch (Orach Chayim 284:3) states that one should be attentive and answer Amen to the berachot of Keriat HaTorah and the Haftarah so that one gets credit for saying the necessary 100 daily berachot. The Mishnah Berurah (Orach Chayim 284:5) notes that accordingly it is a mitzvah for someone who receives an aliyah to recite the berachot aloud so that the congregation can respond Amen.
The Aruch HaShulchan (Orach Chayim 284:12) writes similarly that it is an obligation (“chovah”) for those who receive an aliyah to recite the berachot aloud in order for the congregation to be able to respond Amen. In fact, he rules that “go’arim bo” – we express anger at those who recite the berachot silently.
Despite these rulings, many congregations allow people to say the berachot silently. It is surprising that they are not corrected and told that “lo zu haderech,” such is not proper.