One should not learn Torah or eat a meal from a half-hour before the time for Hanukah candle lighting, until he lights the candles. Our community’s practice is to light the candles around 15-20 minutes after sundown, and so one should not begin learning or eating a meal from around 15 minutes before sundown, which in New York City this time of year is around 4:15pm.
Although eating a meal is forbidden during this time, it is permissible to eat less a Ke’besa of bread, and certainly to eat fruit or "Mezonot" foods. Moreover, if the father will be returning from work later in the evening, the family may eat supper before he arrives, and they do not have to wait for him to light candles. This is the ruling of Hacham Ovadia Yosef.
A person who did not light at the preferred time – which, as mentioned, is 15-20 minutes after sunset, according to our custom – may light even later, even until daybreak, and he may even recite the Berachot. The only condition, however, is that there are people who will see the candles and thus "Pirsumeh Nisa" (publicizing the miracle) will take place. Therefore, if one lights at a time when the candles will be visible, either to people outside or to people inside the home, then he may light and recite the Berachot. If, however, a person arrives home very late at night, and there is nobody to see the candles, he must wake up members of his household so they can be present for the lighting, as otherwise he cannot recite the Berachot. Hacham Bension Abba Shaul (Israel, 1924-1998) rules that two people besides the person lighting and besides his wife must be present for "Pirsumeh Nisa" to be achieved. These two people may be minors, as long as they have reached the age of training in Misvot. Therefore, in the case of a father who returns home very late at night, after everybody is asleep, and he has not yet lit Hanukah candles, he would need to wake up at least two children so he can light with the Berachot. Otherwise, he lights the candles without reciting the Berachot.
Hacham Bension adds that if a person lives alone, and he arrives home late at night, he lights the Hanukah candles without a Beracha.
It should be noted that different opinions exist as to the proper procedure a family should follow if the father cannot be home at the time of the Hanukah candle lighting. Hacham Bension was of the opinion that lighting at the proper time takes precedence over all other considerations. Thus, for example, he maintained that if a person would have to miss the Arbit service in the synagogue by lighting Hanukah candles on time, he should do so. Additionally, he writes, if the father would be returning from work later than the proper time for lighting, a family member should light at the proper time on his behalf. What’s more, according to Hacham Bension, if all the family members will be out of the house at the time for lighting, they should appoint somebody else as their Shaliah ("messenger") to light in their home on their behalf at the proper time. Hacham Bension felt very strongly about the importance of lighting at the proper time, which, in his view, overrides all other considerations.
Others, however, disagree, and maintain that since nowadays we in any event light indoors, we do not need to be that strict with regard to the preferred time for lighting. According to this opinion, a family may light candles when the father arrives home in the evening, even if this occurs later than the preferred time.
According to all opinions, however, one should make an effort to light at the proper time, as stated by the Rama (Rav Moshe Isserles of Cracow, 1530-1572), in his glosses to the Shulhan Aruch (Orah Haim 672:2).
If a person, for whatever reason, missed the lighting one night, he does not make up the missed lighting by lighting the next day, or by adding candles on the next night. However, a missed night of lighting has no impact at all on his obligation on the subsequent nights of Hanukah, and he lights as usual on each of the subsequent nights, with the Berachot. (Hanukah candle lighting differs from Sefirat Ha’omer, in that a missed day of counting prevents one from reciting the Beracha when he counts on subsequent nights.) Hacham Bension Abba Shaul writes that if a person missed a night of lighting and feels a desire to make up what he missed in some way, he can add some oil to the candles on the next night.
Once a half-hour has passed since the lighting of the candles, one may, if he so wishes, blow out the candles, or benefit from the light. Although the Ben Ish Hai (Rav Yosef Haim of Baghdad, 1833-1909) ruled stringently in this regard, Hacham Ovadia followed the opinion of the Shulhan Aruch, that one may extinguish or benefit from the Hanukah candles after a half-hour. Additionally, after a half-hour one may derive personal benefit from the oil. If the candles were extinguished before a half-hour, one may not derive benefit from the oil, unless he had specifically stipulated before lighting the candles that he wishes to use the oil.
Hacham Bension maintained that it is proper, as a measure of stringency, to have the candles burn for longer than a half-hour – specifically, until a half-hour after the time for lighting according to the view of Rabbenu Tam. The time for lighting according to Rabbenu Tam is around one hour later than the time we light the Hanukah candles, and thus following this stringency requires placing enough oil or using large enough wax candles to sustain the flame for an hour-and-a-half. Although this is not required according to the strict Halacha, nevertheless, given that oil and candles nowadays are not expensive, it would be worthwhile to observe this measure of stringency.
Summary: One should not eat a meal with bread starting a half-hour before the time for lighting. However, if the family is waiting for the father to return home and light, they may eat supper in the meantime. Our custom is to light the Hanukah candles 15-20 minutes after sunset, and one should try to light at this time. One who did not light at this time may light anytime later, throughout the night, but if there aren’t at least two people besides him and his wife who will see the candles, the Berachot are not recited. According to one opinion, if a person will not be home at the preferred time for lighting, another family member should light instead of him, or, if necessary, he should appoint somebody else to light in his home in his stead. Others disagree. After the candles have burned for a half-hour, one may extinguish the candles and make personal use of the oil, or make use of the light. It is preferable, though, as a measure of stringency, to have the candles lit for an hour-and-a-half.