Half of New Zealand receives digital TV already by subscribing to Sky TV.
The cost for some households could be hundreds of dollars more than expected.
There are two ways to receive digital TV signals: from satellites, or from mountain-top transmitters, called terrestrial.
Choosing the satellite option has the little-known bonus of enabling viewers to receive two Australian state-owned channels because Australia's Special Broadcasting Service (SBS) uses the same satellite as Freeview.
To view SBS, avoid buying the official Freeview satellite set-top boxes (which plug into your existing TV), unless they have the ability to do a blind scan of the satellite's offerings.
SBS reflects all parts of Australian culture, but recent immigrants seem to be the preferred demographic, with news, documentaries and movies in dozens of languages (with subtitles). SBS gave World Cup soccer fans full 24-hour coverage of every game.
Because Sky TV uses the same satellite as SBS and Freeview, if you have a Sky dish on your house left over from the previous occupant, then plug in your satellite set-top box and enjoy.
SBS could be switched off for New Zealand at any time, but it has been available since 2007.
If you can receive Prime TV, then a terrestrial digital TV set-top box should do the trick.
The advantage of terrestrial digital reception is you are assured of receiving regional broadcasters.
Most new TVs do not need a set-top box.
The main hidden cost of going digital is whether the existing cables from your roof are good enough.
Napier Freeview installation specialist Glen Bidlake says "there is a lot of very old cable out there".
"Some of it just manages, but you won't know whether yours will cope until you plug it in.
"Some of the older aerials might need replacing as well, if they are corroded or have the old cable inside."
He says a typical cable installation should cost about $200 and an aerial up to $150, on top of the set-top box price of about $150. A satellite dish costs about $200.
More hidden expense is involved if you wish to record shows. A weakness with digital TV is not being able to watch one channel while recording another.
Digital recorders are worthwhile just for the TV guide alone. They make recording TV programmes so much easier than the old VCRs, which could only be programmed to record by 15-year-olds with PhDs.
Expect to pay up to $600 for a digital recorder, but it will make a set-top box unnecessary.
"There are some really good recorders that let you record a terabyte of TV programmes, that's a week's viewing," says Glen.
The government agency tasked with helping us make the move to digital TV is called Going Digital.
As the analogue switch-off looms, it is mailing out information to all homes and a Targeted Assistance Package is available for those aged 75 and over with a Community Services Card, recipients of a Veteran's Pension or Invalids' Benefit, or former Veteran's Pension and Invalid's Benefit recipients who transferred to NZ Superannuation at age 65 or over.
Those eligible for the programme receive a set-top box and aerial or satellite dish. The equipment will be installed and training will be provided, together with technical support, for 12 months.
Glen says a lot of people have trouble understanding their new installation and need tutoring.
"I try not to charge - sometimes the time involved ends up costing me money."
It is an area where 15-year-olds may again find themselves useful.