Thieves who steal metal plaques from war memorials or damage monuments during the course of a theft face tougher penalties under new guidelines for judges in England and Wales.
The Sentencing Council also recommends harsher punishments when an item of great sentimental value is stolen.
Historic England welcomed the move, saying the value of heritage "can't be judged in pounds and pence".
More than 91,000 offenders were sentenced for theft last year.
The sentencing guidelines now focus on "additional harm" suffered by victims, with their emotional distress, loss of confidence and any disruption or inconvenience now taken into account.
'Steal from all of us'
Offences involving historic objects being stolen have been specifically recognised as "more serious" by the Sentencing Council for the first time.
The new guidelines say this includes damage to war memorials when thieves steal metal plaques, and theft of objects from a historic shipwreck.
Mark Harrison, national policing and crime adviser for Historic England, said: "When thieves steal metal from heritage assets, such as listed churches, artefacts from the ground or historic stonework from an ancient castle, they are stealing from all of us and damaging something which is often irreplaceable."
Ken Skates, Welsh Deputy Minister for Culture, Sport and Tourism, also welcomed the new rules, saying: "Wales' heritage is precious and significant damage or theft from a site of historic value is often irreversible, meaning a piece of our history is lost forever."
If the items stolen were of "substantial value" to the victim - besides the financial value of stolen items - then the thief could now receive a harsher penalty.
This could include the theft of a mobile phone containing photographs or messages of great sentimental value, or a laptop containing an important piece of work like a PhD, the Sentencing Council said.
"Smartphones can contain a huge amount of personal data, such as photos and messages which can be of great value to their owner even if they do not have financial worth," a spokesman said.
"Theft of a smartphone can also cause great inconvenience to the owner if they lose all their contacts or other essential data or work."
Shop theft and pickpocketing
Jill Gramann, Sentencing Council member and magistrate, said: "The new guidelines will help judges and magistrates deal with this great variety of offences while ensuring that the harm caused to the victim is central to the sentencing decision.
"Thefts are committed for financial gain but can mean much more than financial loss to the victim and we want to ensure sentences take this into account."
Other factors making an offence more serious include thefts that risk causing personal harm, such as stealing electrical cables.
The new guidelines will apply to all kinds of theft offences, such as shop theft, pickpocketing, handling stolen goods and stealing by employees.
And the courts will also have specific guidance for the first time for common offences such as theft of a motor vehicle or bicycle.