Alex

Some of your numbers are quite off and you are also missing out some important items.

Your meal cost at $10 for 3 meals per head per day can only work if you & your wife live like low income families and only eat the cheapest food item in the hawker centre or coffee shop every single day.

For normal middle class lifestyle combination of coffee shop, food court, cafe and the occasional restaurant, you will need to at least double that. FYI a simple meal & drink in food court for 2 costs ~$12-$15 whereas a low to mid end cafe burns $40-$50 for 2 pax.

Meal : 40 * 30 days = $1200

Your telephone bill also not very realistic. Assuming you and your wife both get lower end mobile plans with data, that's going to be ~$40 per subscription.

telephone, phone bills : 40 x 2 lines = $80

Also you are missing out transport, which can cost quite a bit depending on your options. If both of you choose the cheapest public transport, you will need ~$150 and maybe your wife travel less ~$100. If you are targeting taxis everywhere, then generally you need $1-1.2k. For the more expensive option of leasing cars, the cheapest car lease is $1500 per month plus expense so maybe $2000 a month.

Transport: $250 (public), $1000-$1200 (taxi), $2000 (car). For normal middle class lifestyle combination of mainly public plus occasional taxi I would say $400 is realistic.

Also you need to budget for all the daily nity gritty household expenses besides just utilities, conservatively I would say you should put aside at least $200 monthly.

Household miscellaneous: $200

Then on a more personal note, I hope you are not expecting your wife to simply stay at home for 365 days a year. Looking at your income, I don't think she will be able to mix around with the expat spousal community, so I would just assume some normal middle class local recreation.

Wife Outing/Recreation: $300-$500 (this is more personal choice).

Don't forget tax either. As a foreigner, most likely the only income tax deductible you are going to qualify is a general $1k line. On the basis of $90k income, that will will incur an approximate tax bill of $4400.

Tax: $365 monthly

I am assuming in terms of medical & insurance your company covers everything for both you and your spouse. Otherwise you need to set aside some money as well since medical services ain't cheap in Singapore either. Especially if your company never cover major medical for spouse, must buy something for wife. Otherwise one emergency stay in a Singapore hospital without local subsidy can costs 5 or even 6 figure amounts.

In summary, on a household income basis, $7k+ is considered below median (low-middle income) by Singapore standards. However because you incur additional expenses as a foreigner, chances are your income after deducting for necessities will likely be at the end of low income family.

I just lay down the numbers, it's up to you to decide whether this lifestyle is suitable for you and your wife.