Gole vs. golo
The primary difference between these words is regional. While both describe the act of swallowing a specific amount of liquid, gole is the standard term used in Brazilian Portuguese, whereas golo is the standard term used in European Portuguese (Portugal) and other Lusophone countries.
Gole
B1This word is used almost exclusively in Brazil to describe a swallow, a sip, or a gulp of a drink. It can refer to a small taste or consuming a large amount of liquid at once.
Ele tomou um gole de café quente.
(He took a sip of hot coffee.)
Bebi a água toda em um único gole.
(I drank all the water in a single gulp.)
Você quer um gole do meu suco?
(Do you want a sip of my juice?)
Ela deu o último gole na bebida e saiu.
(She took the last sip of the drink and left.)
Desceu tudo de um gole só.
(It all went down in one gulp.)
Golo
B1This is the European Portuguese equivalent used to describe a draft, swallow, or mouthful of liquid. It functions exactly like its Brazilian counterpart but is the preferred pronunciation and spelling in Portugal.
Deu um golo na cerveja antes de falar.
(He took a sip of the beer before speaking.)
Preciso de um golo de água fresca.
(I need a sip of fresh water.)
Bebeu o remédio de um golo.
(He drank the medicine in one gulp.)
Os pequenos golos ajudam a matar a sede.
(Small sips help quench the thirst.)
O vinho foi consumido em grandes golos.
(The wine was consumed in large gulps.)
Summary
To choose the correct word, you simply need to know your audience. If you are speaking with Brazilians, use gole. If you are speaking with Portuguese or African Portuguese speakers, use golo.