Do you have their home phone number?
Stress 'NU-me-ro'. 'Casa loro' = their home.
Ask this when you need someone's landline number. While landlines are less used, many Italian families and businesses still maintain one.
'Numero di casa' = home number (landline). 'Il fisso' = the landline (short for 'telefono fisso', meaning fixed telephone). 'Il cellulare' = the mobile. Many Italians still distinguish between 'ti chiamo al fisso' (I'll call you on the landline) and 'ti chiamo al cellulare'.
Non risponde al cellulare. Provo al fisso.
They're not answering the mobile. I'll try the landline.
Switching to landline.
Hai un numero fisso?
Do you have a landline?
Asking if they have one.
Preferisce essere contattato al fisso o al cellulare?
Do you prefer to be contacted on the landline or mobile?
Formal preference question.
Landlines ('telefoni fissi') in Italy are still maintained by many households, particularly those with elderly residents ('anziani') who prefer them. Italian landline calls are billed differently from mobiles, and calls from mobiles to landlines can be expensive, making it worth knowing both numbers.